User Manual Oscilloscope Lecroy Lc534L

Operator’s Manual

LeCroy LC Series Color Digital Oscilloscopes

Revision K — December 1999

LeCroy Corporation 700 Chestnut Ridge Road Chestnut Ridge, NY 10977–6499 Tel: (914) 578 6020, Fax: (914) 578 5985

LeCroy SA 2, rue du Pré-de-la-Fontaine 1217 Meyrin 1/Geneva, Switzerland Tel: (41) 22 719 21 11, Fax: (41) 22 782 39 15

Internet: www.lecroy.com

Copyright © January 1999, LeCroy. All rights reserved. Information in this publication supersedes all earlier versions. Specifications subject to change.

LeCroy, ProBus and SMART Trigger are registered trademarks of LeCroy Corporation. Centronics is a registered trademark of Data Computer Corp. Epson is a registered trademark of Epson America Inc. I2C is a trademark of Philips. MathCad is a registered trademark of MATHSOFT Inc. MATLAB is a registered trademark of The MathWorks, Inc. Microsoft, MS and Microsoft Access are registered trademarks, and Windows and NT trademarks, of Microsoft Corporation. PowerPC is a registered trademark of IBM Microelectronics. DeskJet, ThinkJet, QuietJet, LaserJet, PaintJet, HP 7470 and HP 7550 are registered trademarks of Hewlett-Packard Company. Manufactured under an ISO 9000 Registered Quality Management System Visit www.lecroy.com to view the certificate.

This electronic product is subject to disposal and recycling regulations that vary by country and region. Many countries prohibit the disposal of waste electronic equipment in standard waste receptacles. For more information about proper disposal and recycling of your LeCroy product, please visit www.lecroy.com/recycle.

LCXXX-OM-E Rev K 1299

LC X X X -O M -E R ev K IS S U E D : D ecem ber 1999 ��

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�� ISSU ED : D ecem ber 1999 LC X X X -O M -E R ev K

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LC X X X -O M -E R ev K IS S U E D : D ecem ber 1999 �

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B L A N K P A G E


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LeCroy recommends that you thoroughly inspect thecontents of the oscilloscope packaging immediately uponreceipt. Compare the contents to the packing list/invoiceshipped with the instrument (and the list on page 1–3).Unless LeCroy is promptly notified of any missing ordamaged item, we cannot accept responsibility for itsreplacement. Contact your nearest LeCroy CustomerService Center or national distributor immediately(telephone numbers are given in the back of this manual).

�� LeC roy w arran ts its osc illoscope products fo r norm al use andopera tion w ith in spec ifica tions fo r a period o f th ree years fromthe da te o f sh ipm ent. C a lib ra tion each year is recom m ended toensure in -spec. perfo rm ance. S pares , rep lacem ent parts andrepa irs a re w arran ted fo r 90 days. T he ins trum ent’s firm w are hasbeen thorough ly tes ted and is thought to be func tiona l, bu t issupp lied w ithout w arran ty o f any k ind covering de ta iledperfo rm ance. P roducts no t m ade by LeC roy are covered so le lyby the w arran ty o f the orig ina l equ ipm ent m anufac turer.

U nder the LeC roy w arran ty, LeC roy w ill repa ir o r, a t its op tion ,rep lace any product re tu rned w ith in the w arran ty period to aLeC roy au thorized serv ice center. H ow ever, th is w ill be done on lyif the product is de term ined a fte r exam ination by LeC roy to bedefec tive due to w orkm ansh ip or m ateria ls , and no t to have beencaused by m isuse, neg lec t o r acc ident, o r by abnorm al cond itionsor opera tion .

�� This warranty replaces all other warranties,expressed or implied, including but not limited to anyimplied warranty of merchantability, fitness, or adequacy forany particular purpose or use. LeCroy shall not be liable forany special, incidental, or consequential damages, whetherin contract or otherwise. The client will be responsible forthe transportation and insurance charges for the return ofproducts to the service facility. LeCroy will return allproducts under warranty with transport prepaid.


��

�� H elp on ins ta lla tion , ca lib ra tion , and the use o f LeC roy equ ipm entis ava ilab le from the LeC roy C ustom er S ervice C enter in yourcountry (telephone num bers are given at the back of this m anual).

�� LeC roy prov ides a varie ty o f cus tom er support serv ices underM ain tenance A greem ents . S uch agreem ents g ive ex tendedw arran ty and a llow c lien ts to budget m a in tenance costs a fte r thein itia l th ree-year w arran ty has exp ired . O ther serv ices such asins ta lla tion , tra in ing , enhancem ents and on-s ite repa irs a reava ilab le th rough spec ia l supp lem enta l support agreem ents .

�� LeCroy is dedicated to offering state-of-the-art instrum ents bycontinually refining and im proving the perform ance of LeCroyproducts. Because of the quick pace at which physical m odificationsm ay be im plem ented, this m anual and related docum entation m aynot agree in every detail w ith the products they describe. Forexam ple, there m ight be sm all discrepancies in the values ofcom ponents that affect pulse shape, tim ing, or offset; and infrequently m inor logic changes. Be assured, however, that thescope itself incorporates the m ost up-to-date circuitry.

LeC roy frequently updates firm w are and so ftw are during

servic ing to im prove scope perfo rm ance, free o f charge during

w arran ty. You w ill be kept in fo rm ed o f such changes, th rough

new or rev ised m anua ls and o ther pub lica tions .

Nevertheless, you should retain this original manual to referto your scope’s unchanged hardware specifications.

�� P lease re tu rn products tha t requ ire m ain tenance to the C ustom erS ervice D epartm ent in your country, o r to an au thorized serv icefac ility. You are respons ib le fo r transporta tion charges to thefac tory, w hereas a ll in -w arran ty p roducts w ill be re tu rned to youw ith transporta tion prepa id . O uts ide the w arran ty period , you w illneed to p rov ide us w ith a purchase order num ber be fore w e canrepa ir your LeC roy product. You w ill be b illed fo r parts and laborre la ted to the repa ir w ork , and fo r sh ipp ing .


��

�� C ontac t the neares t LeC roy S ervice C enter o r o ffice to find ou tw here to re tu rn the product. A ll re tu rned products shou ld beidentified by m ode l and seria l num ber. You shou ld describe thedefec t o r fa ilu re , and prov ide your nam e and contac t num ber. Inthe case o f a p roduct re tu rned to the fac tory, a R eturnA uthoriza tion N um ber (R A N ) shou ld be used. T he R A N can beobta ined by contac ting the C ustom er S ervice D epartm ent.

R eturn sh ipm ents shou ld be prepa id . W e cannot accept C O D(C ash O n D e livery) o r C o llec t R eturn sh ipm ents . W erecom m end a ir fre igh t.

It is im portan t tha t the R A N be c learly show n on the ou ts ide o fthe sh ipp ing package fo r p rom pt fo rw ard ing to the appropria teLeC roy departm ent.

�� T he fo llow ing item s are sh ipped w ith the s tandard configura tionof th is osc illoscope:

� F ron t S cope C over

� 10 :1 10 MΩ ΠΠ005 Πασσιϖε Προβε one per channe l

� ™ Σινγλε−Χηαννελ Αδαπτερ NOT APPLICABLE TOLC374, LC564 OR LC584 SERIES

�

�

�

� R em ote C ontro l M anua l

� H ands-O n G uide

� P erfo rm ance C ertifica te or C a lib ra tion C ertifica te

� D ec la ra tion o f C onform ity

� W arran ty

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�� Wherever possible, please use the original shippingcarton. If a substitute carton is used, it should be rigid andpacked so that that the product is surrounded by a minimumof four inches (10 cm) of shock absorbent material.


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BLANK PAG E

LC X X X -O M -E R ev K ISSU ED : D ecem ber 1999 ��

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�� Wherever a feature is specific or not applicable to aparticular model or series of models, the applicability isindicated as, for example: LC564 AND LC584 SERIES ONLY.See Appendix A for each model’s complete specifications.

��

Each of the four channels of aLeCroy LC Color Digital StorageOscilloscope (DSO) has one ormore 8-bit Analog-to-DigitalConverters (ADCs). Combinechannels by interleaving ADCs tosubstantially increase theinstrument’s acquisition memoryand sampling rate.

�� T he centra l p rocess ing un it (C P U ), a P ow erP C® m ic roprocessor,

perfo rm s the osc illoscope ’s com puta tions and contro ls itsopera tion . A w ide range o f periphera l in te rfaces a llow rem otecontro l, s to rage o f w aveform s and o ther da ta , and prin ting . Asupport p rocessor constan tly m on ito rs the fron t-pane l contro ls .D ata process ing is fas t, w ith da ta e ither trans ferred to d isp laym em ory fo r d irec t w aveform d isp lay or s to red in re fe rencem em ories (see “M em ories” be low ).

�� T he ins trum ent’s A D C arch itec ture is des igned to g ive exce llen t

am plitude and phase corre la tion , m ax im um ana log–to–d ig ita lconvers ion perfo rm ance, la rge record lengths and superio r tim ereso lu tion .

�� T he long acqu is ition m em ories s im p lify s igna l acqu is ition by

produc ing w aveform records tha t a llow deta iled ana lys is over

la rge tim e in terva ls . C om bin ing tw o or four channe ls (FOUR-

CHANNEL COMBINING NOT AVAILABLE ON LC564 SERIES ) increases

acqu is ition m em ory length . T here are four m em ories fo rtem porary s to rage, and four m ore fo r w aveform zoom ing andprocess ing .


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�� R epetitive s igna ls can be acqu ired and s to red a t a R andom

Interleaved S am pling (R IS ) ra te o f 10 G S /s fo r a ll m ode ls except

LC564, LC584, AND LC684 SERIES, w hose R IS ra te is 25 G S /s .

M oreover, th is advanced d ig itizing techn ique enab lesm easurem ent o f repetitive s igna ls w ith an e ffec tive sam pling

in te rva l o f 100 ps , o r 40 ps fo r LC564, LC584, AND LC684 SERIES,

and a m easurem ent reso lu tion o f up to 10 ps (5 ps fo r LC684

SERIES). See Chapter 7.

�� T riggering can be contro lled to a h igh ly spec ia lized degree in

accordance w ith w aveform characteris tics and chosen triggercond itions . M enus and contro ls enab le the se lec tion and se ttingof param eters such as pre- and post-trigger record ing , and o fsequence and ro ll m odes. T he trigger source can be any o f theinput channe ls , line (synchron ized to scope ’s m ain input supp ly)or ex terna l. T he coup ling is se lec ted from A C , LF R E Ject, H FR E Ject, H F , and D C ; the s lope from pos itive and negative . T he

S M A R T T rigger® types o ffe r a w ide range o f soph is tica ted

trigger m odes m atched to spec ia l trigger cond itions and se ts o fcond itions . S ee C hapter 8 .

�� T he osc illoscope ’s au tom atic ca lib ra tion ensures an overa ll

vertica l accuracy o f typ ica lly 1% of fu ll sca le . V ertica l ga in andoffse t ca lib ra tion , and horizonta l (tim e) reso lu tion , take p laceeach tim e the vo lts per d iv is ion se tting is m od ified . In add ition ,period ic and tem pera ture-dependent au toca lib ra tion ensureslong-te rm s tab ility a t the current se tting .

�� The display’s interactive, user-friendly interface is controlled by push-

buttons and knobs to display as m any as eight different waveform sat once. The param eters that control signal acquisition are reportedsim ultaneously. The screen presents internal status andm easurem ent results, as well as operational, m easurem ent, andwaveform -analysis m enus. See Chapters 4 and 16 .

T he la rge d isp lay area presents w aveform s and data us ingA dvanced C o lor M anagem ent. O verlap-m ix ing and contras t-enhancem ent func tions ensure tha t overlapp ing w aveform srem ain d is tinc t a t a ll tim es. B oth pre-se t and persona l co lo rschem es are ava ilab le . S ee C hapter 11 .


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T he A na log P ers is tence™ func tion o ffe rs d isp lay a ttribu tes o f an

ana log ins trum ent w ith a ll the advantages o f d ig ita l techno logy.T he Fu ll S creen func tion expands w aveform grids to fill the en tirescreen. S ee C hapter 11 .

A hard copy o f the screen can be eas ily p roduced a t any tim e bypress ing the fron t-pane l screen-dum p button (see C hapter 12).

�� This is a tru ly d ig ita l ins trum ent. N everthe less the fron t-pane llayout and contro ls w ill be fam ilia r to users o f ana logosc illoscopes (see C hapter 4 ). R ap id response and ins tan trepresenta tion o f w aveform s on the h igh-reso lu tion screen add toth is im press ion .

Four fron t pane l se tups can be s to red in te rna lly and reca lledd irec tly o r by rem ote contro l, thus ensuring rap id fron t pane lconfigura tion . W hen pow er is sw itched o ff, the curren t fron t pane lse ttings are au tom atica lly s to red fo r use w hen the scope istu rned on aga in . S ee C hapter 15 .

�� The oscilloscope has also been designed for rem ote controloperation in autom ated testing and com puter-aided m easurem entapplications. The entire m easurem ent process, including cursor andpulse-param eter settings, dynam ic m odification of front-panelsettings, and display organization, is controlled through the rear-panel industry-standard G PIB (IEEE-488) and standard RS-232-Cports whose connection or serial port are present on m ost of today’spersonal com puters. For further details, please consult your rem otecontrol m anual. See Rem ote Control Manual.

�� A lso v ia G P IB and R S -232-C , the S cope E xp lorer so ftw arein tegra tes the osc illoscope w ith W indow s 95 and W indow s N Tdesk top . It o ffe rs user-friend ly rem ote contro l o f the osc illoscope,copy o f the d isp lay in to W indow s, and the record ing to andstorage in the P C o f fron t-pane l se tups, w h ich can then betransferred back to the osc illoscope. S ee C hapter 12 and theH ands-O n G uide fo r m ore on P C and o ther in te rfaces .


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��

F a stM e m o ry

D is p la yP ro ce s so r

S a m p le& H o ld

T rig g e rL o g ic

ExternalTrigger

CH1

CH2

CH3

CH4

T im e b a se

F a s tM e m o ry

P e a kD e te c t

P e a kD e te c t

P e a kD e te c t

P e a kD e te c t

F a s tM e m o ry

F a s tM e m o ry

S a m p le& H o ld

S a m p le& H o ld

S a m p le& H o ld

P ro g ra m M e m o ry

P o w e r P CM ic ro p ro ce s so rw ith In te g ra te d C a ch e M e m o ry

O p tio n a l

S to ra g e D e v ic e s

C e n tro n ics

R S -2 3 2 -C

G P IB

F ro n t-P a n e lP ro ce s so r

R e a l-Tim eC lo c k

D a ta M e m o r ie s

F lo p p y D isk In te rfa c e

8 -B it A D C (s )

8 -B it A D C (s )

8 -B it A D C (s )

8 -B it A D C (s )


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D is p la yP ro ce s so r

ExternalTrigger

CH1

CH2

CH3

CH4

T im e b a se

P ro g ra m M e m o ry

P o w e r P CM ic ro p ro ce s so rw ith In te g ra te d C a ch e M e m o ry

O p tio n a l

S to ra g e D e v ic e s

C e n tro n ics

R S -2 3 2 -C

G P IB

F ro n t-P a n e lP ro ce s so r

R e a l-Tim eC lo c k

D a ta M e m o r ie s

F lo p p y D isk In te rfa c e

S a m p le& Ho ld

F a s tm e m o ry

F a s tm e m o ry

S a m p le& Ho ld

8 -B it A D C

8 -B it A D C

F a s tm e m o ry

F a s tm e m o ry

T rig g e rL o g ic

S a m p le& Ho ld

S a m p le& Ho ld

8 -B it A D C

8 -B it A D C


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B LA N K P A G E


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Ensure that the operating environment is maintained within thefollowing parameters for safe operation of the oscilloscopewithin specifications:

� Tem perature ........................... 5 to 40 °C (41 to 104 °F)

� Hum idity...................................≤80% R H (non-condens ing)

� A ltitude .....................................≤2000 m (6560 ft)

� O peration ................................. indoor use only

The oscilloscope has been qualified to the following EN 61010-1categories:

� Installation (O vervoltage) Category............. II� Pollution Degree........................................... 2

�� W here the following sym bols or indications appear on the

instrum ent’s front or rear panels, or elsewhere in this m anual, theyalert you to an aspect of safety.

��

CAUTION: Refer to accompanying documents (for safetyrelated information).This symbol appears elsewhere in this manual, as indicated inthe Table of Contents.

WARNING: Risk of electric shock.

x On (Supply)

Off (Supply)

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Earth (Ground) Terminal

Protective Conductor Terminal

Alternating Current Only

Chassis Terminal.

Earth (Ground) Terminal on BNC Connectors.

WARNINGDenotes a hazard. If a WARNING is indicated on theinstrument, do not proceed until its conditions areunderstood and met.

�� Any use of this instrument in a manner not specified by themanufacturer may impair the instrument’s safety protection.The oscilloscope has not been designed to make directmeasurements on the human body. Users who connect aLeCroy oscilloscope directly to a person do so at their ownrisk.

�� The oscilloscope operates from a 115 V (90 to 132 V) or 230 V(180 to 250 V) AC (~) power source at 45 to 66 Hz.


��

No voltage selection is required because the instrum entautom atically adapts to the line voltage that is present.

�� The power supply of the oscilloscope is protected against short-circuit and overload by m eans of two fuses (T 6.3 A, 250 V) locatedabove the m ains plug.

D isconnect the power cord before inspecting or replacing a fuse.O pen the fuse box by inserting a sm all screwdriver under the plasticcover and prying it open. For continued fire protection at all linevoltages, replace only w ith fuses of the specified type and rating.

�� The oscilloscope has been designed to operate from a single-phasepower source, w ith one of the current-carrying conductors (neutralconductor) at ground (earth) potential. M aintain the ground line toavoid electric shock.

None of the current-carrying conductors m ay exceed 250 V rm s withrespect to ground potential. The oscilloscope is provided with athree-wire electrical cord containing a three-term inal polarized plugfor m ains voltage and safety ground connection. The plug’s groundterm inal is connected directly to the fram e of the unit. For adequateprotection against electrical hazard, this plug m ust be inserted into am ating outlet containing a safety ground contact.

�� M aintenance and repairs should be carried out exclusively by aLeCroy technician (see Chapter 1). C leaning should be lim ited to theexterior of the instrum ent only, using a dam p, soft cloth. Do not usechem icals or abrasive elem ents. Under no circum stances shouldm oisture be allowed to penetrate the oscilloscope. To avoid electricshock, unplug the instrum ent from the power outlet before cleaning.

�� Risk of electrical shock: No user-serviceable parts inside.Leave repair to qualified personnel.

�� Connect the oscilloscope to the power outlet and switch it on, usingthe power O n/O ff button located near the left-hand corner of theinstrum ent below the screen. W hen the instrum ent is switched on,auto-calibration and a test of the oscilloscope’s ADCs and m em oriesare perform ed. The full testing procedure takes approxim ately 10seconds, then a display w ill appear on the screen.

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BLANK PAG E


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LC684ONLY


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The front-panel controls are divided into four main groupsof buttons and knobs:

• SYSTEM SETUP• CHANNELS• TIMEBASE + TRIGGER• ZOOM + MATH

Other buttons access special features.�� Dark gray m enu entry buttons (also present in other groups of

controls) provide access to the m ain on-screen m enus and theinstrum ent’s acquisition, processing, and display m odes. TheSCREEN DUM P and CLEAR SW EEPS buttons copy or print thescreen display, and restart operations that require severalacquisitions. (See page 4–5.)

�� T he seven untitled buttons vertica lly a ligned bes ide the screen,R E T U R N and the tw o linked ro ta ry knobs enab le on-screenm enu se lec tion . (S ee fo llow ing pages.)

�� This group of controls offers selection of displayed traces andadjustm ent of vertical sensitivity and offset. (See Chapter 5.)

�� These controls allow direct adjustm ent of tim e/division, trigger leveland delay, as well as access to the “T IM EBASE” and “TRIG G ER”m enu groups. (See Chapters 6, 7, and 8.)

�� This group controls trace selection, m ovem ent, definition, andexpansion with Zoom and Math functions. (See Chapters 9 and 10.�

�� This blue button autom atically adjusts the scope to acquire anddisplay signals on the active input channels. (See page 4–6.)

�� This green button accesses the unique Analog Persistence™feature. (See Chapter 11.)

�� Redraws the grid to fill the entire screen. (See Chapter 11 .)

�� Part 2, “Gett ing Started,” in the �� for more information about the front panel,and a complete run-through of the controls.


��

��

On-screen menus — the panels along the right-hand side ofthe screen — are used to select specific scope actions andsettings. All other on-screen text is for information only. Themenus are broadly grouped according to function. Thename of each menu group is shown at the top of the columnof menus. Individual menus also have names at the top oftheir frames.E ach m enu e ither conta ins a lis t o f item s or op tions — functionsto be se lec ted or variab les m od ified — or perfo rm s a spec ificac tion w hen se lec ted . M enus tha t perfo rm ac tions are ind ica tedby cap ita lized tex t, as in the exam ple a t le ft.

��

W hen you press a m enu entry bu tton , the se tup configura tion fo rits particu la r g roup o f func tions is im m edia te ly d isp layed as am enu group. O nce accessed, these m enus are contro lled by them enu buttons and the tw o m enu knobs (illus tra ted a t le ft).

A m enu button is ac tive and can be pressed to m ake se lec tionsw henever a m enu is v is ib le bes ide it on-screen. T he tw o m enuknobs w ork w ith the tw o m enu buttons to w h ich they are jo inedby lines . B oth contro l the m enus curren tly show n bes ide them .B uttons and knobs are used e ither fo r se lec ting en tire m enus,particu la r item s from m enus, fo r m oving up or dow n th roughm enu lis ts , o r fo r chang ing the va lues lis ted in m enus.

S om e m enus have o thers beh ind them . T he ir p resence isind ica ted by a heavy ou tline or shadow on the fron t m enu, asillus tra ted a t le ft. P ress ing the correspond ing m enu buttonrevea ls the back m enu. P ress ing the R E T U R N button aga ind isp lays the fron t m enu.

A change o f a m enu value norm ally changes the screen becausethe new value is im m ediately used in acquisition settings,processing, or display.


��

�� T he ac tiva ted se lec tion is h igh ligh ted in the m enu. P ress thecorrespond ing m enu button and the fie ld w ill advance to h igh ligh tand se lec t the next item on the m enu. H ow ever, if there is on lyone item on a m enu, p ress ing its bu tton w ill have no e ffec t.

W here a m enu is assoc ia ted w ith one o f the tw o m enu knobs,tu rn ing th is knob in one d irec tion or the o ther w ill cause these lec tor to m ove up or dow n the m enu lis t.

M enus tha t span tw o m enu buttons can be opera ted us ing bothbuttons. P ress ing the low er o f the tw o w ill m ove the se lec tordow n the m enu lis t, w h ile p ress ing the upper bu tton w ill m ove these lec tor up the lis t.

A n arrow on the s ide o f a m enu fram e ind ica tes tha t by press ingthe button bes ide th is a rrow , the se lec tor can be m oved fa rtherup or dow n the lis t. T he arrow ’s d irec tion show s w hether these lec tor w ill m ove up or dow n. A rrow s m ay a lso ind ica te tha tthere are add itiona l und isp layed item s above or be low the m enulis t. T he respective arrow w ill d isappear w hen the se lec tor is a tthe very beg inn ing or end o f the lis t.

A s in the exam ples a t le ft, som e m enu button and knobcom binations contro l the va lue o f a continuous ly ad jus tab levariab le . T he knob is then used to se t its va lue , w h ile the buttone ither se lec ts a va lue or m akes a s im ple change in it.

S till o ther m enu button and knob com binations contro l the va lueof severa l continuous ly ad jus tab le variab les , w ith the knob usedto se t the va lue and the button to h igh ligh t it.

�� When the oscilloscope is placed in the remote state,the REMOTE ENABLE menu will be displayed. It willcontain the command “GO TO LOCAL,” which is activatedby a menu button if the action is applicable. This is the onlyway to manually turn off the REMOTE ENABLE menu. Theoscilloscope does not need to be in the remote state toaccept remote commands.


��

��

Besides the menu buttons and knobs described on theprevious pages, the SYSTEM SETUP controls include themenu entry buttons and others for copying displays,reporting instrument status, and restarting multiple-acquisition operations.

is used to go back to the preceding displayed m enu group.

O r it returns the display to a higher-level, or prim ary m enu. W henpressed at the highest possible m enu level, however, the buttonswitches off that m enu.

Each of the dark gray m enu entry buttons activates a m ajor set ofon-screen m enus. (M enu entry buttons that are part of other controlgroups are described in later chapters.)

gives you access to the “D ISPLAY SETUP” group of

m enus, which control display m ode, grids, intensities, Dot Join, andPersistence m enus (Chapter 11).

gives you access to the “UTILIT IES” m enus, which control

hardcopy setups, G PIB addresses and special m odesof operation (Chapter 12).

WAVEFORM g iv e s yo u a c c e s s to th e

“S T O R E W ’F O R M ” m e n u s th a t a re u s e d fo rs to r in g w a v e fo rm s in in te rn a l o r e x te rn a lm e m o ry (Chapter 13).

WAVEFORM g iv e s yo u a c c e s s to th e

“RECALL W ’FORM” m enus that are used to retrievewaveform s stored in internal or external m em ory (Chapter13).


��

g iv e s yo u a c c e s s to the “C U R S O R S ” se tup m enus,

w h ich are used to m ake prec ise cursor m easurem ents on traces,and the “M E A S U R E ” m enus, w h ich are used fo r p rec iseparam eter m easurem ents and pass/fa il tes ting (Chapter 14).

g iv e s yo u a c c e s s to the “P A N E L S E T U P S ” m enus,

w h ich are used fo r sav ing and reca lling an ins trum entconfigura tion (Chapter 13).

g iv e s yo u a c c e s s to th e “S T A T U S ” m enu, w h ich

sum m arizes the ins trum ent’s s ta tus fo r acqu is ition , sys tem , andother func tions (Chapter 16).

�� T his bu tton prin ts o r p lo ts the screen d isp lay to an on-line

hardcopy device , v ia the G P IB , R S -232-C or C entron ics in te rfaceports , o r d irec tly to a bu ilt-in therm al g raph ics prin te r. You cana lso save screen d isp lays as da ta files on floppy d isk , m em orycard , o r portab le hard d isk .

W hen S C R E E N D U M P is p ressed, a ll d isp layed in fo rm ation w illbe cop ied. H ow ever, it is poss ib le to copy the w aveform s w ithoutthe grid by tu rn ing the grid in tens ity to zero , us ing the “D isp layS etup” m enu.

W hile a screen dum p is tak ing p lace — ind ica ted by the on-screen “P R IN T IN G ” or “P LO T T IN G ” m essage — you can cance lit by p ress ing S C R E E N D U M P a second tim e. It takes a m om entfo r the bu ffe r to em pty be fore copying s tops (C hapter 12).

�� B y resetting the sw eep counter(s ) to zero , th is bu tton res tarts

opera tions tha t requ ire severa l acqu is itions (sw eeps) inc lud ingaverag ing , ex trem a, pers is tence, param eter s ta tis tics , andpass/fa il tes ting .


��

Press the blue AUTO SETUP button to automatically scalethe timebase, trigger level, offset, and volts/div to provide astable display of repetitive signals.This button operates only on active channels. If no channelsare switched on, and no signals are detected, AUTO SETUPwill operate on all channels, switching all of them on. Ifsignals are detected on several channels, the channel withthe lowest number determines which timebase and triggersource are selected for setup.Signals detected must have an amplitude from 5 mV to 40 V,a frequency greater than 50 Hz, and a duty cycle greaterthan 0.1%.

�� To perform a general reset of the instrument,simultaneously press the AUTO SETUP, top menu,and RETURN buttons:

� � ��

The oscil loscope wil l revert to its default power-up settings.

(top m enu)


��

��

The grid area of the screen and the fields surrounding it provide a variety of useful information,and specific commands and functions.


��

Real-Time Clock: P ow ered by a ba tte ry-backed rea l-tim e c lock ,

th is fie ld d isp lays the curren t da te and tim e.

Displayed Trace Label: T his fie ld ind ica tes each channe l o r

channe l d isp layed, the tim e/d iv and vo lts /d iv se ttings , and cursorread ings w here appropria te . It ind ica tes the acqu is itionparam eters se t w hen the trace w as captured or p rocessed,w hereas the A cqu is ition S um m ary fie ld (see be low ) ind ica tes thecurrent se tting .

Acquisition Summary: T h is fie ld show s the tim ebase, vo lts /d iv ,

p robe a ttenuation , and coup ling fo r each channe l, w ith these lec ted channe l h igh ligh ted. It ind ica tes the current se tting ,w hereas the acqu is ition param eters tha t w ere se t w hen the tracew as captured or p rocessed are ind ica ted in the D isp layed T racelabe l (above).

Trigger Level: T he arrow s on bo th s ides o f the grid m ark the

trigger vo ltage re la tive to g round poten tia l.

Trigger Delay: Located be low the grid , th is fie ld ind ica tes the

trigger tim e re la tive to the trace . T he de lay can be ad jus ted from

zero to ten grid d iv is ions (p re-trigger), o r zero to −10 000 (post-

trigger) o ff-screen. T he pre-trigger de lay appears as the upw ard-po in ting arrow , w hereas post-trigger is g iven as a de lay inseconds.

Trigger Status: T his fie ld show s sam ple ra te and trigger re -

arm ing s ta tus (A U T O , N O R M A L, S IN G LE , S T O P P E D ). T hesm all rec tang le flashes to ind ica te tha t an acqu is ition has beenm ade.

Trigger Configuration: T his fie ld conta ins an icon ind ica ting the

type o f trigger, and provides in fo rm ation on the trigger’s source ,s lope, leve l and coup ling , and o ther in fo rm ation w henappropria te .


��

Trace and Ground Level: T his is the trace num ber and ground-

leve l m arker.

��(not shown)

Time and Frequency: T his a rea d isp lays the tim e and frequency

re la tive to cursors be low the grid . For exam ple , w hen theabso lu te tim e cursor (the c ross-ha ir) is ac tiva ted by se lec ting itfrom the “M E A S U R E ” m enu group, th is fie ld d isp lays the tim ebetw een the cursor and the trigger po in t.

Message: T his a rea above the grid is used to d isp lay a varie ty o f

m essages inc lud ing w arn ings, sys tem ind ica tions , and titlesshow ing the ins trum ent’s curren t s ta tus .

# # #


� ��

��

These controls let youselect displayed tracesand adjust verticalsensitivity and offset.

�� Press these buttons to

display or switch off thecorresponding channeltrace. W hen a channelis switched on, O FFSETand VO LTS/DIVcontrols are assigned tothis, the active channel.

�� Th e s e b u tto n s a s s ig n

a ll ve r t ic a l c o n tro ls too n e c h a n n e l,re g a rd le s s o f th ec h a n n e l d is p la ye d .T h e s e le c te d c h a n n e ln u m b e r is h ig h lig h te din th e A c q u is it io nS u m m a ry f ie ld (s e ep re v io u s c h a p te r) .

�� T his bu tton autom atically adjusts offset and volts/div to m atch the

active channel’s input signal.

�� T h is k n o b ve r t ic a lly p o s it io n s th e a c tive c h a n n e l.

�� This button selects the vertical sensitivity either in a 1–2–5 sequence

or continuously (see VAR, below). From the “SPECIAL M O DES”m enu, you can select the effect of gain changes on the acquisitionoffset.

�� The variability knob allows you to determ ine whether the VO LTS/DIV

knob will m odify the vertical sensitivity in a continuous m anner or indiscrete 1–2–5 steps.


��

The form at of the vertical sensitivity in the Acquisition Sum m ary field(bottom left of screen) shows whether the VO LTS/DIV knob isoperating in continuous or stepping m ode.

�� This m enu entry button accesses the “Coupling” m enus (see next

section).


��

��

Press to select a coupling level that adapts theoscilloscope’s input impedance to the impedance of thedevice under test. This button also accesses the menus thatlet you select the� coupling and grounding of each input channel� ECL or TTL gain, offset, and coupling that have been

preset for the channel shown� bandwidth limit for all channels� probe attenuation of each input channel

��

This function selects the input channel’s coupling. If an overload isdetected, the instrum ent w ill autom atically set the channel to thegrounded state. You can then reset the m enu to the desiredcoupling.

��

W hen NO RM AL is highlighted, pressing the corresponding m enubutton sets the offset, Volts/div, and input coupling to display ECLsignals. Press the button a second tim e to display the settings forTTL signals. Press the button a third tim e to return the settings tothose used during the last m anual setup of the channel.

��

This function turns the bandwidth lim it O ff or selects a lim it. Thebandwidth can be reduced from the m axim um to either 200 M Hz or25 M Hz, or 30 M Hz (–3dB), depending on the m odel (see AppendixA). Bandwidth lim iting is useful for reducing signal and system noiseor preventing high-frequency aliasing, reducing any high-frequencysignals that m ay cause aliasing in single-shot applications, forexam ple. This m enu is titled “G lobal BW L” if the G lobal BW L isactivated; that is, the lim it that you set w ill apply to all channels.W hen a lim it can be set individually for each channel, it appears as


��

“BW L” if the G lobal BW L is deactivated. See Chapter 12, “SpecialM odes.”

��

T his func tion se ts the probe a ttenuation fo r the input channe l.(S ee the fo llow ing sec tion fo r p robe deta ils .)

��

� In the AC position signals are coupled capacitively, thus blocking the input signal’sDC component and limiting signal frequencies below 10 Hz.

� In the DC position all signal frequency components are allowed to pass through, and1 MΩ or 50 Ω can be selected as the input impedance.

� The maximum dissipation into 50 Ω is 0.5 W. Whenever this maximum is reached• inputs will automatically be grounded• an overload message will be displayed in the Acquisition Summary field• the overload condition can be reset by removing the signal from the input and again

selecting the 50 Ω input impedance from the menu• “Grounded” will be highlighted in the “Coupling” menu


��

��

Calibrate the passive probe supplied with the oscilloscope asfollows (see also the separate instruction sheet provided withthe probe):1. Turn on the oscilloscope.2. If you are using the HF-compensation ground lead,

insert the lead’s pins into the probe head, and connectthe probe to one of the input channels/BNC connectors.

3. Attach the lead’s alligator clip to the CAL BNC’s ground(outer ring) and touch the tip to its inner conductor.Alternatively, if you are using the 11-cm ground lead,attach the supplied BNC adapter to the CAL BNC, andinsert the probe tip into the adapter after connecting theprobe to an input channel.The CAL signal in both cases will be a 1-kHz squarewave, 1 V p–p

4. Set the channel coupling to DC 1 MΩ, using the“Coupling” menu. Then press the TRACE ON/OFFbutton to activate the desired trace.

5. Press to set up the oscilloscope.

If the d isp layed s igna l is overshot o r undershot, you can ad jus tthe probe by inserting the sm all sc rew driver supp lied w ith theprobe package in to the trim m er on the probe ’s barre l and tu rn ingit c lockw ise or counterc lockw ise to ach ieve the op tim a l squarew ave.

��®�� LeC roy’s P roB us sys tem provides a com ple te m easurem entso lu tion from probe tip to osc illoscope d isp lay. T h is in te lligen tin te rconnection be tw een LeC roy osc illoscopes and a w ide rangeof accessories is ach ieved us ing a bus tha t fo llow s P h ilips ’ I

2C

LeCroy PP005 passiveprobe


��

pro toco l. P roB us o ffe rs im portan tadvantages over s tandard B N Cand probe-ring connections .

For exam ple, the system ensurescorrect input coupling by auto-sensing the probe type, thuselim inating the guesswork anderrors that occur when attenuationor am plification factors are setm anually.

ProBus also allows control of transparent gain and offset from thefront panel, particularly useful for FET and current probes. It uploadsG ain and offset correction factors from the ProBus EPRO M S onFET probes, autom atically com pensating to achieve fully-calibratedm easurem ents.

��This function is used to select the input channel’s coupling. If anoverload is detected, the instrum ent w ill autom atically set the channelto the grounded state. The m enu can then be reset to the desiredcoupling.

��W hen NO RM AL is highlighted, pressing the corresponding m enubutton sets the offset, Volts/div, and input coupling to display ECLsignals. Press the button a second tim e and the settings for TTLsignals are given. And a third tim e returns the settings to those usedat the last m anual setup of the channel.

��

Use this function to turn off the bandwidth lim it or to select a lim it.The bandwidth can be reduced from the m axim um to either200 M Hz or 25 M Hz, or 30 M Hz (–3dB), depending on your LCm odel (see Appendix A). Bandwidth lim iting is useful for reducingsignal and system noise or preventing high-frequency aliasing,reducing any high-frequency signals that m ay cause aliasing insingle-shot applications, for exam ple. This m enu appears as “G lobalBW L” if the G lobal BW L is activated; that is, the lim it that you setapplies to all channels. W hen a lim it can be set individually for each

Illustrated at right: a LeCroycurrent probe with ProBusconnection.


��

channel, it appears as “BW L” if the G lobal BW L is deactivated. SeeChapter 12, “Special M odes.”

� W hen a FE T probe is used, “P robe sensed… ” appearsautom atica lly. W hen o ther P roB us probes are used, th is isredefined.

# # #


��

B LA N K P A G E


� ��

��

These controls let you adjust time/division, trigger level anddelay; and to access the “TIMEBASE” and “TRIGGER” menugroups. See Chapter 7 for descriptions of the TimebaseModes that are affected by these controls. See Chapter 8 fortrigger details.

�� T his bu tton ha lts the

acqu is ition in any o f thethree re -arm ing m odes:A U T O , N O R M A L orS IN G LE .

• P ress the S T O Pbutton to prevent theosc illoscope fromacqu iring a news igna l.

• If you press S T O Pw hile a s ing le -shotacqu is ition is inprocess, the las tacqu ired s igna l iskept.

• If you press S T O Pafte r an R ISacqu is ition hasstarted , theacqu is ition is ha lted ,and a partia lw aveformreconstruc tion is done.

• If you press S T O P w hen the acqu is ition is in R o ll M ode, theincom ple te acqu is ition da ta is show n as if a trigger hadoccurred . (LC584 AND LC684 SERIES: You can tu rn on zoomexpans ions a fte r p ress ing S T O P .) In S equence M ode,press ing S T O P s tops the tim ebase and show s a ll newsegm ents .


��

�� P ress th is bu tton to p lace the ins trum ent in A uto M ode: the scope

autom atica lly d isp lays the s igna l if no trigger qu ick ly occurs .

• If a trigger does occur w ith in th is tim e, the osc illoscopebehaves as in N orm al M ode.

• If you press A U T O in R IS M ode, the ins trum ent ends theacqu is ition and d isp lays it each second (som e requ iredsegm ents m ay be m iss ing).

• If you press A U T O in R o ll M ode, the osc illoscope sam plesthe input s igna ls continuous ly and indefin ite ly. T heacqu is ition has no trigger, bu t you can s top it w henever youdes ire .

• If you press A U T O in S equence M ode, the acqu is ition ends ifthe tim e betw een tw o consecutive triggers exceeds som ese lec tab le tim eout. T he next acqu is ition then s ta rts fromS egm ent 1 . (S ee C hapter 12 , “S pec ia l M odes.”)

�� P ress th is bu tton to continuous ly update the screen w h ile a va lid

trigger is p resent. If there is no va lid trigger, the ins trum entpreserves the las t s igna l, and d isp lays the w arn ing “S LO WT R IG G E R ” in the T rigger S ta tus F ie ld .

• If you press N O R M A L in R o ll M ode, the acqu is ition endsw hen the las t needed data a fte r a trigger have been taken.T he d isp lay pauses to show the en tire w aveform . It thengoes back in to R o ll M ode w h ile it w a its fo r the next trigger.

• If you press N O R M A L in S equence M ode, the acqu is itionends a fte r the las t segm ent is acqu ired . T he next acqu is itions tarts im m edia te ly. S equence W R A P in N orm al is the sam eas in S ing le -S hot M ode.


��

�� P ress th is bu tton to p lace the ins trum ent in S ing le -S hot M ode,

w here it w a its fo r a s ing le trigger to occur, then d isp lays thes igna l and s tops acqu iring . If no trigger occurs , you can press thebutton aga in to see the s igna l w ithout a trigger.

• If you press S IN G LE in R IS M ode, the ins trum ent w a its fo r a llthe trigger events needed to bu ild one s igna l be fore it s tops .A s m any as 4000 trigger events m ay be requ ired .

• S ing le-S hot R o ll M ode behavior is the sam e as s tandardS ing le-S hot behavior bu t w ithout the need to press the buttona second tim e to d isp lay the s igna l. H ow ever, you can pressthe button aga in to end the acqu is ition w ith the currentava ilab le da ta .

�� T his knob ad jus ts the pre- o r pos t-trigger de lay. P re-trigger

ad jus tm ent is ava ilab le from zero to 100% of the fu ll tim e sca le inincrem ents o f 1% . T he pre-trigger de lay is illus tra ted by thevertica l a rrow sym bol a t the bo ttom o f the grid . P ost-triggerad jus tm ent is ava ilab le from 0 to 10 000 d iv is ions in increm entso f 0 .1 d iv is ion . Labe led in un its o f seconds, the post-trigger-de layva lue is d isp layed in the T rigger D e lay fie ld .

�� T his bu tton se ts the trigger de lay a t zero , the trigger ins tan t a t the

le ft-hand edge o f the grid .

�� T his knob se lec ts the tim e per d iv is ion in a 1–2–5 sequence. T he

tim e/d iv se tting is d isp layed in the A cqu is ition S um m ary fie ld .

�� T his knob ad jus ts the trigger th resho ld . T he am plitude o f trigger

s igna ls and the range o f trigger leve ls is lim ited :

� ±5 screen d iv is ions w ith a channe l as the trigger source

� ±0.5 V or ±1.2 V (LC564, LC584, AND LC684 SERIES) w ith E X T

as the trigger source

� ±5 V w ith E X T /10, o r ±6 V w ith E X T /5 (LC564 AND LC584SERIES ) as the trigger source

� inac tive w ith L ine as the trigger source

T rigger sens itiv ity is be tte r than one-th ird screen d iv is ion .


��

�� T his m enu entry bu tton ca lls up the “T IM E B A S E ” m enus

(described in the next chapter).

�� T his m enu entry bu tton ca lls up “T R IG G E R S E T U P ” m enus

(described in C hapter 8 ).

# # #


� ��

��

Depending on the timebase, you may choose fromthree sampling modes: Single-Shot, RIS (RandomInterleaved Sampling), or Roll mode. Furthermore, fortimebases suitable for Single-Shot or Roll mode, theacquisition memory can be subdivided into user-defined segments to give Sequence mode.

�� S ing le-S hot is the d ig ita l s to rage osc illoscope ’s bas ic acqu is itionm ethod.

A n acqu ired w aveform is a series o f m easured vo ltage va luessam pled a t a un ifo rm ra te from the input s igna l. In S ing le-S hotm ode, th is acqu is ition is a series o f m easured data va luesassoc ia ted w ith a s ing le trigger event. A cqu is ition is typ ica llys topped a t a fixed tim e a fte r the event. T h is fixed tim e isdeterm ined by the trigger de lay, and is m easured by thetim ebase c lock . T he horizonta l pos ition o f a w aveform isdeterm ined by us ing the trigger event to de fine tim e zero .

B ecause each o f the osc illoscope ’s channe ls has one or m oreA D C s, the vo ltage on every input channe l is sam pled andm easured a t the sam e ins tant. T h is a llow s very re liab le tim em easurem ents am ong the d iffe rent channe ls .

You can se t the trigger de lay anyw here w ith in a range tha t a llow sthe w aveform to be sam pled from w ell be fore the trigger event upto the m om ent it occurs (100% pre-trigger). A lte rnative ly, thew aveform can be sam pled a t the equ iva len t o f 10 000 d iv is ions— the current tim e/d iv (post-trigger).

For fas t tim ebase se ttings , the m ax im um S ing le-S hot sam plingra te is used, w ith h igher sam pling ra tes ach ieved by com bin ingchanne ls (see page 7–5). For s low er tim ebases, the sam plingra te is decreased, bu t the num ber o f da ta sam ples rem ains thesam e. (S ee A ppend ix A fo r spec ifica tions .)


��

�� W ith s low tim ebases, sam ple ra te decreases and very shortevents such as g litches can be m issed if they occur be tw eensam ples . T o avo id th is spec ia l c ircu itry ca lled P eak D etec t cancapture the s igna l enve lope to a reso lu tion o f 2 .5 ns . T h is doesnot, how ever, des troy underlying s im u ltaneous ly captured da taon w h ich advanced process ing can s till be perfo rm ed. (S eem enus on page 7–6.)

R andom In terleaved S am pling (R IS ) is an acqu is ition techn iquetha t a llow s e ffec tive sam pling ra tes h igher than the m ax im umsing le -shot sam pling ra te . It is used on repetitive w aveform s w itha s tab le trigger. T he osc illoscope ’s m ax im um effec tive sam pling

ra te o f 10 G S /s (25 G S /s fo r LC564, LC584, AND LC684 SERIES )

can be ach ieved w ith R IS by acqu iring 20 s ing le -shot acqu is itions(b ins) a t 500 M S /s . T hese b ins are pos itioned approx im ate ly

0 .1 ns apart (40 ps on LC564, LC584, AND LC684 SERIES). T he

process o f acqu iring the b ins and sa tis fying the tim e constra in t isa random one. T he re la tive tim e betw een A D C sam pling ins tan tsand the event trigger p rov ides the necessary varia tion , m easured

by the tim ebase to 10-ps (5 ps fo r LC684 SERIES) reso lu tion .

Buildup of an RIS waveform.

��

NNOOTT AAVVAAIILLAABBLLEE OONNLLCC556644,, LLCC558844,, OORR LLCC668844SSEERRIIEESS

Segment 1

Segment 3

Segment 2

Final capture


��

O n average, 104 trigger events a re needed to com ple te an R ISacqu is ition . B ut som etim es m any m ore are needed. T hesesegm ents are in te rleaved to p rov ide a w aveform tha t covers atim e in te rva l tha t is a m u ltip le o f the m ax im um s ing le -shotsam pling ra te . H ow ever, the rea l-tim e in te rva l over w h ich thew aveform data are co llec ted is m uch longer, and depends on thetrigger ra te and the des ired leve l o f in te rleaving . T he osc illoscopeis capab le o f acqu iring approx im ate ly 40 000 R IS segm ents persecond.

�� Incom ing po in ts in s ing le -shot acqu is itions tha t have a su ffic ien tlylow data ra te can be d isp layed in rea l tim e, us ing R o ll m ode. O na ll m ode ls a t tim ebase se ttings ≥0.5 s /d iv (≥10 s /d iv fo r traces o f500 000 po in ts or m ore* on a ll m ode ls except the LC564, LC584,AND LC684 SERIES) the osc illoscope ro lls the incom ing datacontinuous ly across the screen until a trigger event is de tec tedand the acqu is ition is com ple te . T h is w orks in the sam e w ay as as trip -chart recorder: the la tes t da ta is used to update the traced isp lay. W aveform M ath and P aram eter ca lcu la tions areperform ed on the com ple ted w aveform s, a fte r the rea l-tim ed isp lay has s topped.

�� In S equence m ode, the com ple te w aveform cons is ts o f a num bero f fixed segm ents acqu ired in S ing le -S hot m ode (see A ppend ix Afor the lim its ). You can de term ine the num ber o f segm ents to beacqu ired , and each segm ent can be ind iv idua lly se lec ted andused in p rocess ing .

S equence m ode o ffe rs a num ber o f un ique capab ilities .D eadtim e betw een trigger events fo r consecutive segm ents canbe kept to under 50 µs , in contras t to the m illisecond or evenlonger tim e in terva ls norm ally found betw een consecutive s ing le-shot w aveform s. C om plica ted sequences o f events over la rgetim e in terva ls can be captured in fine deta il, w h ile theun in teres ting periods betw een the events are ignored. A nd tim em easurem ents can be m ade betw een events on se lec tedsegm ents us ing the fu ll p rec is ion o f the acqu is ition tim ebase.

* E ven w hen rea l-tim e d isp lay is no t poss ib le , the da ta w ill con tinue to

be acqu ired .


��

T rigger tim e s tam ps are g iven fo r each o f the segm ents , us ingthe “T ext & T im es S ta tus” m enu (see C hapter 16). E achind iv idua l segm ent can be zoom ed or used as input to m athfunctions (see C hapter 10).

T he tim ebase se tting in S equence m ode is used to de term ine theacqu is ition dura tion o f each segm ent: 10 x tim e/d iv . T h is se tting ,a long w ith the des ired num ber o f segm ents , m ax im um segm entlength , and to ta l ava ilab le m em ory are used to de term ine theactua l num ber o f sam ples or segm ents , and tim e or po in ts .H ow ever, the d isp lay o f the com ple te w aveform w ith a ll itssegm ents m ay not en tire ly fill the screen.

S equence m ode can a lso be used in rem ote opera tion to take fu lladvantage o f the scope ’s h igh da ta-transm iss ion capab ility,overlapp ing the transm iss ion o f one w aveform w ith itssuccessor’s acqu is ition (see the R em ote C ontro l M anua l fo rde ta ils ).

�� S equence m ode is norm ally used fo r the acqu is ition o f a des irednum ber o f segm ents , a fte r w h ich the w aveform acqu is ition isautom atica lly te rm inated. However, segm ents can a lso beacqu ired continuous ly in S equence m ode, us ing W rap, w ith theo ldest segm ents progress ive ly overw ritten by new segm ents in afirs t in -firs t ou t sequence. A m anua l S T O P order o r tim eoutcond ition is then used to te rm inate the acqu is ition (fo r m ore onS equence and W rap behavior, see page 7–11).

�� The behavior of is modified in both Roll and Sequence modes (refer to theprevious chapter and page 7–11).�� To ensure low deadtime betweensegments, you must avoid pushing buttons and turningknobs during the acquisition.

NNOOTT AAVVAAIILLAABBLLEE OONNLLCC556644,, LLCC558844,, OORR LLCC668844SSEERRIIEESS


��

��

For fast timebases, interleaving of the oscilloscope’s ADCsby the combining of channels greatly boosts both samplerate and memory length.

�� Depending on your scope m odel, a pair of channels can becom bined on channel 2 or 3, w ith channels 1 and 4 disabled oravailable only for triggering (see Note). O n these paired channels them axim um sam pling rate is doubled and the record length isincreased by four or five tim es, depending on the m odel.

�� A ll channe ls can be com bined on a s ing le , p re-de fined channe l(NOT ON LC564 SERIES ), w h ile the o thers a re e ither d isab led or,depend ing on the m ode l, rem ain ava ilab le fo r triggering on ly (seeN ote). T he in te rleaving o f A D C s and acqu is ition m em ory bycom bin ing a ll four channe ls ach ieves up to four tim es the in itia lm ax im um sam pling ra te , and a t leas t four tim es the recordlength .

M ode ls in the LC334, LC534 LC574, and LC684 SERIES com bine

channe ls by m eans o f a s im p le adapter.

W hen a ll channe ls a re com bined on a LC374 SERIES m ode l, the

sam pling ra te is doub led on C hanne l 2 and the record lengthincreases five fo ld .

MODELS IN THE LC564, LC584 SERIES s im ila rly do not requ ire anadapter. In add ition , they can com bine the ir A D C s on any inputchanne l us ing A uto-C om bine m ode. In th is m ode, w h ich isactiva ted by se lec ting “A utom atic ” from the “C hanne l U se” m enu(see page 7–7), a ll ava ilab le m em ory is a lloca ted to a s ing le ,ac tive d isp layed channe l, p rov ided no o ther channe l is d isp layedor re ferenced in the P aram eter o r M ath S etup. If tw o traces ared isp layed or re fe renced, sam pling and m em ory resources w ill bed iv ided equa lly be tw een them . If m ore than tw o traces ared isp layed or re fe renced, the resources w ill be sp lit equa lly am onga ll four channe ls .

S ee the M ax im um S am ple R ate and A cqu is ition M em ory tab le inA ppend ix A fo r the spec ifica tions fo r each m ode l.

�� (SERIES LC564,LC584 ONLY) Channels arecombined to increasesample rate or memory sizeor both in order to captureand view a signal in all itsdetail. When combined,those channels (like the EXTBNC input) that are notinvolved in the combinationremain available fortriggering, even though theyare not displayed. It ispreferable to select“Automatic” (not availableon LC684 SERIES) to combinechannels and have theremaining acquisitionchannels available fortriggering. The channelsavailable for triggering onlyare indicated by “trig only”in the Acquisition SummaryField.


��

��

�� Press to choose Single-Shot, RIS. or Sequencemodes to combine channels and increase sample rate andrecord length on most models; or use Peak Detect and theexternal clock, where available.“T IM EBASE” indicates the num ber of points acquired, sam ple rate,and total tim e span.

LLCC333344,, LLCC337744,, LLCC553344,, LLCC557744,, aanndd LLCC668844 SSEERRIIEESS

��

For selecting either of the two principal m odes of acquisition:

� Single Shot displays data collected during successive single-shot acquisitions from the input channels. This m ode lets youcapture non-recurring or very low repetition-rate eventssim ultaneously on all input channels (see page 7–1).

� RIS (Random Interleaved Sam pling) achieves a higher effectivesam pling rate than Single-Shot, provided the input signal isrepetitive and the trigger is stable (see page 7–2).

��

Use this feature to select Internal or external (ECL, OV, TTL) clockm odes (see page 7–8).

��

Use this feature to com bine channels or activate Peak Detect m ode(refer to page 7–2). S e lec t 4 to com bine a ll input channe ls , o r 2 tocom bine a pa ir o f channe ls on bo th C H 2 and C H 3 (see prev iouspage). Peak Detect cap tures h igh-speed events (no t ava ilab le onLC684 SERIES).

��Use this feature to turn the Sequence m ode on or off, or to selectWrap whereby new segm ents are acquired continuously. W ithSequence turned On, the corresponding m enu knob is used tochoose the num ber of segm ents (see page 7–10).


��

��Use this feature to select the m axim um num ber of sam ples to beacquired, using the associated m enu knob. See Appendix A form odel m axim um s.

LLCC556644 AA NN DD LLCC558844 SSEERRIIEESS��

Use this feature to select one of the two principal m odes of acquisition:

� Single Shot displays data collected during successive single-shotacquisitions from the input channels. This m ode lets you capturenon-recurring or very low repetition-rate events sim ultaneously onall input channels (see page 7–1).

� RIS (Random Interleaved Sam pling) achieves a higher effectivesam pling rate than Single-Shot does, provided the input signal isrepetitive and the trigger is stable (see page 7–2).

��This feature selects Internal or “external” clock m odes (see page7-9).

��S elec t 4 to ac tiva te a ll input channe ls , o r 2 to com bine a pa ir o fchanne ls on bo th C H 2 and C H 3 . S e lec t 1 (NOT AVAILABLE ONSERIES LC564 ) to com bine all channels on CH 2 alone. Automaticoptim izes allocation of sam ple rate and acquisition m em ory acrossthe channels: all available resources are allocated to a singledisplayed channel provided none of the other channels is displayedor referenced in the Param eter or M ath Setup. This auto-com binem ode is also the best choice when using a rem aining acquisitionchannel for triggering (see page 7–5).

��This selection turns Sequence m ode on or off. W hen Sequencem ode is turned on, the corresponding m enu knob is used to choosethe num ber of segm ents (see page 7–10).

��This feature selects the m axim um num ber of sam ples to beacquired, using the associated m enu knob. See Appendix A for them axim um num ber of sam ples for each m odel.


��

LLCC333344,, LLCC337744,, LLCC553344,, LLCC557744 SSEERRIIEESS

�� T hese m enus appear w hen an ex terna l c lock m ode (E C L, O V ,T T L) is chosen from “S am ple C lock ”.

��T his m enu is inac tive w hen the ex terna l sam ple c lock is be ingused. Single-Shot is se lec ted by de fau lt.

��T his fea ture se lec ts a descrip tion o f the s igna l app lied to the E X TB N C connector fo r the s tandard sam ple c lock up to 100 M H z.T he ris ing edge o f the s igna l is used to c lock the A D C s o f theosc illoscope. T he e ffec tive th resho lds fo r sam pling the input a re

†:

E C L ............................... −1.3 V

0V ................................. 0 .0 V

T T L ................................ +1 .5 V

R P (R ear P ane l), w hen show n‡, spec ifies tha t the 50–500 M H z

externa l c lock connected to the rear pane l is to be used as thesam ple c lock .

��T his fea ture se lec ts the input coup ling fo r the ex terna l c locks igna l.

��This feature turns Sequence m ode on or off, or selects Wrap toacquire new segm ents continuously. W hen Sequence On or Wrapis selected, the corresponding m enu knob is used to choose thenum ber of segm ents (see page 7–10). Neither trigger tim e stam psnor the AUTO sequence tim e-out feature are available when externalclock is used, nor is intersegm ent dead tim e guaranteed.


† External clock m odes are available only if the EXT trigger is not the trigger

source.‡ W ith C K TR IG O ption on ly — see tha t op tion ’s ded ica ted O pera to r’s

M anua l (LC XXX-C K TR IG ).


��

LLCC556644,, LLCC558844,, AANNDD LLCC668844 SSEERRIIEESS OOPPTTIIOONNAALL

��T his m enu is inac tive w hen A N externa l sam ple c lock is be ingused. Single-Shot is se lec ted by de fau lt.

��This feature selects the External clock m ode. “External” specifiesthat the DC to 500 M Hz external clock, which is connected to theinstrum ent through the rear panel, is to be used as the sam ple clock.The rising edge of the signal clocks the ADCs. The effectivethreshold for sam pling the input is 0.0 V.

��W hen External is se lec ted , 4 channe ls is the on ly cho iceava ilab le .

��T his fea ture tu rns S equence m ode on or o ff when new segm entsare acquired continuously. W ith Sequence On, the correspond ingm enu knob is used to choose the num ber o f segm ents (see page7–10). N e ither trigger tim e s tam ps nor A U T O sequence tim e-outfea ture are ava ilab le w hen ex terna l c lock is used, nor isin te rsegm ent dead tim e guaranteed.


��The external clock’s time/div is expressed in samples per division, as is thetrigger delay, which can be adjusted normally. No attempt is made to measure thetime difference between the trigger and the external clock, so successiveacquisitions of the same signal can appear to jitter on the screen.The oscilloscope requires a fixed number of pulses (typically 50) to recognize theexternal clock signal. The acquisition is halted only when the trigger conditions havebeen satisfied and the appropriate number of data points have been accumulated.Any adjustment to the time/division knob automatically returns the oscilloscope tonormal (internal) clock operation.


��

�� T his is used fo r S equence m ode.

��

T his m enu is inac tive w hen S equence m ode is be ing used.Single-Shot is se lec ted by de fau lt.

��(OPTIONAL ON LC564 AND LC584 SERIES)

Use this feature to select Internal or external (ECL, OV, TTL) clockm odes (see page 7–8 or 7–9).

��

LC334, LC374, LC534, LC574 AND LC684 SERIES: This featurecom bines channels or activates Peak Detect m ode (see page 7–2),on m odels where these features are available. S e lec t 4 to use a llinpu t channe ls o r 2 to com bine a pa ir o f channe ls on bo th C H 2and C H 3 . Peak Detect cap tures h igh-speed events (no tava ilab le on LC684 SERIES).

LC564 AND LC584 SERIES ONLY (not show n; see m enus on page7–7 )� S elec t 4 to ac tiva te a ll input channe ls or 2 to com bine a pa iro f channe ls on bo th C H 2 and C H 3 . S e lec t 1 (NOT AVAILABLE ONSERIES LC564 ) to com bine all channels on CH 2 alone. Automaticoptim izes allocation of sam ple rate and acquisition m em ory acrossthe channels: all available resources are allocated to a singledisplayed channel provided none of the other channels is displayedor referenced in the Param eter or M ath Setup. This auto-com binem ode is also the best choice when you are using a rem ainingacquisition channel for triggering (see page 7–5).

��

This feature turns Sequence m ode on or off, or selects Wrap (ifavailable) to acquire new segm ents continuously. W hen On or Wrapis chosen, the associated m enu knob is used to choose the num berof segm ents.

��

Along with the corresponding button or knob, this feature selects them axim um record length, in sam ples, for each segm ent. SeeAppendix A for m odel m axim um s.


��

�� In S equence m ode, p ress ing each o f the T IM E B A S E +T R IG G E R bu ttons m entioned here has particu la r e ffec ts on theacqu is ition .

• W hen you press , the oscilloscope fills the chosen

num ber of segm ents and then stops the acquisition. However, it

w ill not stop until you press if there are not enough

trigger events to fill the segm ents.

• P ress to fill the segm ents . W hen a ll a re filled , the

data is p rocessed and d isp layed. T hen, if m ore trigger eventsoccur, the acqu is ition w ill res tart from S egm ent 1 .

• In add ition , if you press , w hen the tim e betw een

tw o consecutive triggers exceeds a prese lec ted tim e-outva lue , the acqu is ition res tarts from S egm ent 1 . (S ee C hapter12, “S pec ia l M odes.”)

�� O n m ode ls w ith Wrap, the segm ents can be filled continuous ly,w ith the o ldes t segm ent overw ritten by the new est one, un til youpress the S T O P button . T he las t n segm ents are then d isp layed.A nother w ay to te rm inate the W rap sequence is w ith the A U T Obutton : the acqu is ition is s topped w hen the tim e betw een tw oconsecutive triggers exceeds a prese lec ted tim e-out va lue .

# # #


��

B LA N K P A G E

LC X X X -O M -E R ev K IS S U E D : D ece m ber 1999 ��

� ��

TRIGGER SETUP

Edge

SMART

��

Your oscilloscope offers many distinctive and usefultechniques for triggering on, and capturing, data. Theserange from simple edge trigger to the advanced, multiple-input SMART Trigger®.T hree triggering m odes are ava ilab le : A U T O , N O R M A L, and

S IN G LE . A dd itiona lly, S T O P le ts you cance l the acqu is ition

process a t an y tim e. A ll m odes are d irec tly access ib le th roughthe ir respective fron t-pane l bu ttons .

�� M ake trigger ad jus tm ents d irec tly us ing the fron t-pane l contro ls

and the tr igger m enus.

Rotate — for example — to adjust the trigger level of thesingle trigger source or, for Pattern Trigger, the highlighted trace.

P ress ing g ives you

access to advanced trigger

opera tions, such as chang ing the

g litch w id th or the ho ld-o ff tim eout,

w h ich are perfo rm ed us ing the

T R IG G E R S E T U P m enu group,represented here schem atica lly (F ig .8–1). O nce you have m od ified the

trigger configura tion , the changes are

s tored in te rna lly in a non-vo la tile

m em ory.

S ee C hapter 6 fo r m ore abou t theseand the o ther tr igger contro ls .

Figure 8–1. Main Trigger Menus.

��describestriggeringoperations, andoffers hints on howto perform them.Along with thestandard menudescriptions, theschematics showthe trigger-menustructure, and thediagrams explainhow the maintriggers work.See also the triggerchapters in the“Hands-On Guide”.

�� ISSU ED : D ece m ber 1999 LC X X X -O M -E R ev K

��

��

A variety of triggers for specific applications can be chosenfrom the two main trigger groups, Edge and SMART Trigger.

�� In the Edge group of m enus, trigger conditions are defined by thevertical trigger level, coupling, and slope. Edge triggers use relativelysim ple selection criteria to characterize a signal. They are m ostuseful for triggering on sim ple signals (see next page and page8–34).

�� T he S M A R T Trigger types a llow add itiona l qua lifica tions to beset be fore a tr igger is genera ted . T hese qua lifica tions can beused to capture rare phenom ena such as g litches or sp ikes,spec ific log ic s ta tes , o r m iss ing b its . A qua lifica tion m ight inc ludetrigger genera tion on ly on a pu lse w ider o r narrow er than a user-spec ified lim it. O r it m ight requ ire — to take ano ther exam ple —three tr igger sources exceed ing spec ific leve ls fo r a m in im umtim e.

G enera lly speak ing , S M A R T T rigger o ffe rs a varie ty o f triggerqua lifica tions , based on the ab ility to

• count a specified number of events

• m easure tim e in te rva ls

• recognize a pattern input

S M A R T exp lanations s ta rt page 8–9 and m enus 8–35.

��, examples of which are illustratedthroughout this chapter, allow immediate on-screen recognition ofthe current trigger conditions. There is a symbol for each Edge andSMART Trigger. The more heavily-marked transitions on thesymbolic waveform indicate the slope on which the trigger will begenerated. And the symbols are annotated by information on thetrigger settings.


��

��

Selecting “Edge” and its menus (Fig. 8–2) causes the scopeto trigger whenever the selected signal source meets thetrigger conditions. The trigger source is defined by thetrigger level, coupling, slope or hold-off. Certain of thesebasic conditions applicable for SMART Trigger are alsoselected in “Edge” (see menu descriptions starting on page8–34).The symbol above represents an edge trigger, with positive slope— the highlighted edge — defined as the trigger condition.

Figure 8–2. Edge Trigger Menus (see page 8–34).

Edge

Trigger on

C oup ling

S lopeP os, N eg,

and W indow depend ing on m ode l

D C , A C , LFR E J, H FR E J, H F

1, 2 , 3 , 4 , E xt, E xt10 ,

o r E xt5 depend ing on m ode l,

L ine

H o ldo ff O ff, T im e , E vents


��

�� T h e t r ig g e r s o u rc e m a y b e o n e o f th e fo l lo w in g :

� T he acqu is ition channe l s igna l (C H 1 , C H 2 , C H 3 or C H 4)cond itioned fo r the overa ll vo ltage ga in , coup ling , andbandw id th .

� T he line vo ltage tha t pow ers the osc illoscope (L IN E ). T h iscan be used to p rov ide a s tab le d isp la y o f s igna lssynchronous w ith the pow er line . C oup ling and leve l a re no tre levant fo r th is se lec tion .

� T he s igna l app lied to the E X T B N C connector (E X T ). T h iscan be used to trigger the osc illoscope w ith in a range o f±0.5 V on E X T and ±5 V w ith E X T /10 as the tr igger source .O r, on the LC564, LC584, AND LC684 SERIES: ±1.2 V fo r E X Tand ±6 V w ith E X T /5 as trigger source .

In addition to the EXT BNC connector, acquisition channels thatare not used when channels are com bined for greater sam plerates or m em ory can be used for triggering (see C hapter 7,“Com bining C hannels”).

�� Leve l defines the source vo ltage a t w h ich the trigger c ircu it w illgenera te an event (a change in the inpu t s igna l tha t sa tis fies thetrigger cond itions). T he se lec ted trigger leve l is assoc ia ted w iththe chosen trigger source . N ote tha t the tr igger leve l is spec ifiedin vo lts and norm ally rem ains unchanged w hen the vertica l ga inor o ffse t is m od ified .

T he A m plitude and R ange o f the tr igger leve l a re lim ited asfo llow s:

� ±5 screen d iv is ions w ith a channe l as the trigger source

� ±0.5 V , o r ±1.2 V fo r the LC564, LC584, AND LC684 SERIESw ith E X T as the trigger source

� ±5 V w ith E X T /10, o r ±6 V w ith E X T /5 as the trigger sourceon the LC564, LC584, AND LC684 SERIES

� none w ith L IN E as the trigger source (zero c ross ing is used)

�� Once specified, Trigger Level and Coupling are the onlyparameters that pass unchanged from trigger mode to triggermode for each trigger source.

AAVVAAIILLAABBLLEE OONNLLYYOONN LLCC556644,, LLCC558844 AANNDDLLCC668844 SSEERRIIEESS


��

�� T his is the particu la r type o f s igna l coup ling a t the input o f thetrigger c ircu it. A s w ith the tr igger leve l, the coup ling can beindependently se lec ted fo r each source. T hus, chang ing thetrigger source can change the coup ling . T he types o f coup lingthat you can se lec t a re :

� DC: A ll the s ignal’s frequency com ponents are coupled to thetrigger c ircuit for h igh-frequency bursts, or where the use of ACcoupling would shift the effective trigger level.

� AC: The s ignal is capacitively coupled, DC levels are rejectedand frequencies below 50 H z attenuated (�10 H z for the LC564,LC584, AND LC684 SERIES).

� LF REJ: The s ignal is coupled through a capacitive h igh-passfilter network. DC is rejected, and signal frequencies below50 kH z are attenuated (�100 M H z for the LC564, LC584, ANDLC684 SERIES). For stable triggering on m edium - to h igh-frequency s ignals.

� HF REJ: S ignals are DC -coupled to the trigger c ircuit. A low-pass filter network attenuates frequencies above 50 kH z. Thisis used for triggering on low frequencies.

� HF: This is to be used only when necessary for triggering onhigh-frequency repetitive s ignals �300 M H z, w ith a m axim umtrigger frequency of �500 M Hz (�1 G H z for the LC564, LC584,AND LC684 SERIES). HF is autom atically overridden and set toAC when it is incom patible w ith other trigger characteristics(and SM ART Trigger). O nly one slope is available.

�� Slope determ ines the d irection of the trigger voltage transition that isused to generate a particu lar trigger event. L ike coupling, theselected slope is associated w ith the chosen trigger source.

�� W ithout hold-off, the tim e between each successive trigger eventwould be lim ited only by the input signal, the coupling, and theoscilloscope’s bandwidth. However, som etim es a stable display ofcom plex repetitive waveform s can be achieved by p lacing acondition on this tim e. This is a hold-off, which can be expressedeither as a period of tim e or an event count. Hold-off disables thetrigger circuit for a given period of tim e, or events (an event is thenum ber of occasions on which the trigger condition is m et) after thelast trigger occurred. The trigger w ill again occur when the hold-offhas elapsed and the other specified conditions are m et. Hold-off isused to obtain a stable trigger for repetitive, com posite waveform s.For exam ple, if the num ber or duration of sub-signals is known, theycan be disabled by choosing an appropriate hold-off value.


��

�� T h is is th e m in im u m tim e b e tw e e n tr ig g e rs (F ig . 8 – 3 ) . A

tr ig g e r is g e n e ra te d w h e n th e tr ig g e r c o n d it io n is m e t a f te rth e s e le c te d h o ld -o f f d e la y f ro m th e la s t tr ig g e r . T h e t im in g

fo r th e d e la y is in it ia l ize d a n d s ta r te d o n e a c h tr ig g e r .

Figure 8–3. Edge Trigger with Hold-off by Time. The bold edges on the trigger source indicate a positive slope. Thebroken upward-pointing arrows show potential triggers that would occur were other conditions met, while the bold

ones show where triggers actually occur when the hold-off time has been exceeded.

This example represents a positive edge triggerlevel of 0.008 V and a hold-off time of 50 ns.

H old-o ff tim e H old-o ff tim e

Trigger Source: Positive Slope

Trigger can occur

Generated Trigger

Trigger

E vent

T rigger

E vent

T rigger

E vent

T rigger in itia tes

ho ld -o ff tim er


ho ld -o ff tim er


��

�� Hold-off by events is initia lized and started on each trigger(F ig . 8 – 4 ) . A trigger is generated when the trigger condition is m etafter the selected num ber of events from the last trigger. An event isdefined as the num ber of tim es the trigger condition is m et after thelast trigger. For exam ple, if the num ber selected is two, as it is inFigure 8–4, the trigger w ill occur on the third event. From 1 to99 999 999 events can be selected.

Figure 8–4. Edge Trigger with Hold-off by Events (two events in this example). The bold edges on the triggersource indicate a positive slope. The broken, upward-pointing arrows indicate potential triggers, while the bold

ones show where triggers actually occur after the hold-off expires.

This example indicates a hold-off of 37 events.

H o ld -o ff by 2 events H o ld -o ff by 2 events


Trigger can occur

G enera ted T rigger

E vent

#1

E vent

#2

E vent

#2

E vent

#1

Trigger

E vent

T rigger

E vent

T rigger

E vent


ho ld -o ff tim er

T rigger

in itia tes

ho ld -o ff

tim er


��

T he W indow T rigger (F ig . 8 – 5 ) a l lo w s th e d e f in it io n o f a

w in d o w re g io n w h o s e b o u n d a r ie s e x te n d a b o v e a n d b e lo w

th e s e le c te d tr ig g e r le v e l. A trigger event occurs w hen the

s igna l leaves th is w indow reg ion in e ither d irec tion and passesin to the upper o r low er reg ion . T he next trigger w ill occur if the

s igna l aga in passes in to the w indow reg ion . For a trigger to

occur, the tim e tha t the s igna l spends w ith in the w indow m ust be

at leas t 0 .5 ns .

Figure 8–5. Edge Window Trigger: triggers when the signal leaves the window region.

This example shows the trigger level andthe range of the window region.

��AAVVAAIILLAABBLLEE OONNLLYYOONN LLCC556644,, LLCC558844 ,, AANNDDLLCC668844 SSEERRIIEESS

WIN

DO

W R

EGIO

N

Trigger Level

Triggers

Time

Lower Region

Upper Region


��

��

SMART Trigger types allow additional qualifications before atrigger is generated. Depending on the oscilloscope model, itmay include triggers adapted for glitches, intervals, abnormalsignals, TV signals, state- or edge-qualified events, dropouts,patterns, “runts,” and slew rate.

�� Generally, a glitch is a pulse that is m uch faster than the observedwaveform . G litch Trigger (Fig. 8–6) is used to capture narrow pulsesless than or equal to, or greater than or equal to, a given tim e lim it.

The example above shows a pulse width of ≤ 10 ns.

Figure 8–6. Glitch Trigger Menus (see page 8–36).

Glitch

Trigger on

C oup ling

A t end o fN eg, P os

pu lse

D C , A C , LFR E J, H FR E J

1, 2 , 3 , 4 , E xt, E xt10 ,


P a tte rn

W id th : less

than or equa lto

O ff, T im e

W id th :

grea te r than

or equa l to

O ff, T im e


��

G litch

W id th

Generated Trigger

G litch

W id th

W id th

S e lected

Trigger Source

Trigger can occur

W idth

S e lected

�� Digita l e lectronics c ircuits norm ally use an internal c lock. For testingpurposes a g litch can be defined as any pulse of w idth sm aller thanthe c lock period or half-period. G litch Trigger has a broad range ofapplications in d ig ita l and analog electronic developm ent, ATE, EM I,te lecom m unications, and m agnetic m edia studies.

T his G litch T rigger se lec ts a m ax im um pu lse w id th (F ig . 8–7). Itis genera ted on the se lec ted edge w hen the pu lse w id th is lessthan or equa l to the se lec ted w id th . T he tim ing fo r the w id th isin itia lized and res tarted on the oppos ite s lope to tha t se lec ted.O n the LC564, LC584, AND LC684 SERIES, g litches as short as600 ps can be triggered on , and w id ths o f 600 ps to 20 s can bese lec ted . O n the o ther m ode ls , w id ths o f be tw een 2 .5 ns and 20s can be se lec ted , bu t typ ica lly triggering w ill occur on g litches1 ns w ide .

Figure 8–7. Glitch Trigger: here on a pulse width less than or equal to thewidth selected. The broken upward arrow indicates a potential trigger, while

the bold one shows where the actual trigger occurs.

��


��

�� S e lec ting “G litch” and se tting w id th cond itions can a lso enab le

the exc lus ion o f events tha t fa ll in o r ou t o f a se lec ted range o f

w id th . T h is is an exc lus ion tr igger (F ig . 8–8). O n ly pu lses ou ts ide(less-than-or-equa l-to o r g rea ter-than-or-equa l-to ) th is range w ill

genera te a trigger event. A lte rna tive ly, you m ay dec ide to trigger

on ly on those pu lses in the range itse lf and exc lude a ll those

outs ide it. T he tim ing fo r the w id th is in itia lized and res tarted on

the s lope oppos ite the se lec ted edge. W id ths o f the sam e va lues

as fo r G litch T rigger can be se lec ted (see prev ious page).

Figure 8–8. Exclusion Trigger. In this example, only pulses outside theboundaries of the width range, those of ≤ 25.0 ns or ≥ 27.5 ns in length, willbe captured. Note the “OR” in the “width ≥” menu, which changes to “&”when triggering only within the range.

�� E xc lus ion T riggers a llow you to spec ify a s igna l’s norm al w id th orperiod . W ith the scope ins truc ted to ignore the norm ally shapeds igna ls and trigger on ly on abnorm al ones, it can con tinuous lysearch fo r c ircu it fa ilu res .


��

�� W hereas G litch T rigger perfo rm s over the w id th o f a pu lse ,In te rva l T rigger (F ig . 8 – 9 ) perfo rm s over the w id th o f an in te rva l.A n in te rva l corresponds to a the s igna l dura tion (the period)separa ting tw o consecutive edges o f the sam e po larity: pos itiveto pos itive edge; nega tive to nega tive edge. Interval T riggercaptures intervals that are shorter or longer than a g iven tim e lim it. Inaddition, a w idth range can be defined to capture any interval thatfalls in or out of the specified range — an Exclusion Trigger byInterval.

Figure 8–9. Interval Trigger Menus (see page 8–38).

�� In te rva l T rigger is he lp fu l fo r de term in ing m iss ing cyc les ortrans itions , and fo r ignoring unw anted s igna l re flec tions.

Interval

Trigger on

C oup ling

B etw eenN eg, P os

edges


1, 2 , 3 , 4 , E xt, E xt10 ,


P a tte rn

In te rva l:

less than o r

equa l to

O ff, T im e

In te rva l:

g rea te r than

or equa l to

O ff, T im e


��

�� For this Interval T rigger, generated on a tim e interval sm aller thanthe one selected, a m axim um interval between two like edges of thesam e slope — positive, for exam ple — is chosen (F ig . 8 – 1 0 ) . Thetrigger is generated on the second (positive) edge if it occurs w ithinthe selected interval. The tim ing for the interval is initialized andrestarted whenever the selected edge occurs. In te rva ls o f be tw een10 ns and 20 s (2 ns and 20 s fo r the LC564, LC584, AND LC684SERIES ) can be se lec ted .

Figure 8–10. Interval Trigger that triggers when the interval width is smallerthan the selected interval. The broken, upward-pointing arrow indicates a

potential trigger, while the bold one shows where the actual trigger occurs —on the positive edge within the selected interval.

This example shows a positive slopeand interval of ≤ 1.99 ms selected.

Generated Trigger

S elected

In te rva l


Trigger can occur

S elected

In te rva l

In te rva l W id thIn te rva l

W id th


��

�� For th is In te rva l T rigger, genera ted on an in te rva l la rger than theone se lec ted , a m in im um in te rva l be tw een tw o edges o f thesam e s lope is se lec ted (F ig . 8–11). T he trigger is genera ted onthe second edge if it occurs a fte r the se lec ted in te rva l. T hetim ing fo r the in te rva l is in itia lized and res tarted w heneve r these lec ted edge occurs . In te rva ls o f be tw een 10 ns and 20 s (2 nsand 20 s fo r the LC564, LC584. AND LC684 SERIES ) can be

se lec ted .Figure 8–11. Interval Trigger that triggers when the interval width is larger

than the selected interval. The broken upward-pointing arrow indicates apotential trigger, while the bold one shows where the actual trigger occurs —

on the positive edge after the selected interval.

This example shows a positive slope andinterval of ≤ 258 ns selected.

In terva l W id th

Generated Trigger

S elected

In te rva l


Trigger can occur

S elected

In te rva l

In te rva l

W id th


��

�� This In te rva l T rigger is genera ted w henever an in te rva l be tw een

tw o edges o f the sam e s lope fa lls w ith in a se lec ted range (F ig .

8 – 1 2 ) . T he tim ing fo r the in te rva l is in itia lized and res tartedw henever the se lec ted edge occurs . In te rva ls o f be tw een 10 ns

and 20 s (2 ns and 20 s fo r the LC564, LC584, AND LC684SERIES ) can be se lec ted .

Figure 8–12. Interval Trigger that triggers when the interval falls within theselected range: T1 = the range’s lower time limit; T2 = its upper limit. Thebroken upward-pointing arrow indicates a potential trigger, while the boldone indicates where the actual trigger occurs — on the positive edge withinthe selected range.

This example shows a positive slope,range limits of ≥ 10.0 ns and ≤ 5.4 �s,selected.

In te rva l W id th

Generated Trigger

Trigger can occur


0 0T1 T1T2 T2

RangeRange

In te rva l

W id th


��

�� This Interval Trigger is generated whenever an interval between twoedges of the same slope falls outside a selected range (Fig. 8–13). Thetrigger is generated on the second edge if it occurs after the selectedinterval range. The timing for the interval is initialized and restartedwhenever the selected edge occurs. Intervals of between 10 ns and 20 s(2 ns and 20 s for the LC564, LC584, AND LC584 SERIES ) can beselected.

Figure 8–13. Interval Trigger that triggers when the interval falls outside theselected range: T1 = the range’s lower time limit; T2 = its upper limit. Thebroken upward-pointing arrow indicates a potential trigger, while the boldone shows where the actual trigger occurs, on the positive edge outside the

selected range.

This example shows a positive slope, andrange limits of ≤ 10.0 ns and ≥ 347.5 nsselected. “OR” means that intervals aboveor below the range have been targeted.

In te rva l W idth

Generated Trigger

Trigger can occur


0 0T1 T1T2 T2

RangeRange

In te rva l

W id th


��

�� P atte rn T rigger (F ig . 8 – 1 4 ) enab les tr iggering on a log ica l

com bination o f the five inputs C H 1 , C H 2 , C H 3 , C H 4 and E X T .

T h is com bination , ca lled a pa tte rn , is de fined as the log ica l A N Dof trigger s ta tes . A trigger s ta te is e ither h igh or low : h igh w hen a

trigger source is g rea ter than the trigger leve l (th resho ld ) and low

w hen less than it (F ig . 8 – 1 5 ) . For exam ple , a pa tte rn cou ld be

defined as present w hen the tr igger s ta te fo r C H 1 is h igh , C H 2

is low , and E X T is irre levant (X or don ’t care). If an y one o f these

cond itions is no t m et, the pa tte rn s ta te is cons idered absent.

H o ld-o ff lim its from 10 ns to 20 s (2 ns–20 s fo r the LC564,LC584, AND LC684 SERIES ) o r from 1 to 99 999 999 events can be

selected.

Figure 8–14. Pattern Trigger Menus (see page 8–43).

Pattern

Trigger on

P atte rn

w ith

C oup ling D C , A C , LFR E J, H FR E J

1, 2 , 3 , 4 , E xt

E xiting, E n te ring

Leve l L , H , X , (Leve l va lue)

O ff, T im e , E vtsH o ldo ff


��

�� P atte rn T rigger can be used in d ig ita l des ign fo r the tes ting o fcom plex log ic inputs o r da ta transm iss ion buses.

Figure 8–15. Pattern Trigger: triggers when all pattern conditions are met.Bold, upward-pointing arrows show where triggers occur.

Information summarizing the pattern setup is displayed.

CH 1

Generated Trigger (Pattern Entering)

Pattern 1H*2L

Thresho ld

CH 2

Generated Trigger (Pattern Exiting)

Thresho ld

H igh

H igh

Low

Low


��

�� O nce the pattern is defined, one of two transitions can be used togenerate the trigger. W hen the pattern begins, called entering thepattern, a trigger can be generated. A lternatively, a trigger can begenerated when the pattern ends, called exiting the pattern.

W ith pattern triggering, as in s ingle source, e ither of these

qualifications can be selected: H old-off for 10 ns up to 20 s (2 ns–

20 s for the LC564, LC584, AND LC684 SERIES ), or Hold-off for 1 to

99 999 999 events.

W hen set to Pattern Trigger, the oscilloscope always checks thelogic AN D of the defined input logic states. However, w ith the helpof de M organ's laws, the pattern becom es far m ore generalized.

Consider the im portant exam ple of the B i-level or W indow PatternTrigger. B i-level im plies the expectation of a s ingle-shot signal onwhich the am plitude w ill go in either d irection outs ide a knownrange. To set up a B i-level Pattern trigger, connect the s ignal to twoinputs: C hannels 1 and 2 or any other pair that can be triggered on.For exam ple, the threshold of CH 1 could be set to +100 m V andthat of C H 2 at −200 m V. The B i-level T rigger w ill occur if theoscilloscope triggers on CH 1 for any pulse greater than +100 m V,or on CH 2 for any pulse less than –200 m V. For im provedprecis ion, the gains of the two channels should be at the sam esetting.

In Boolean notation we can write:

Trigger C H 1 C H 2= +

that is, trigger when entering the pattern C H 1 = high O R C H 2 =low .

B y de M organ's theorem th is is equivalent to:

Trigger C H 1 C H 2= ⋅

that is, trigger when exiting the pattern CH 1 = low AN D CH 2 =high. This configuration can be easily program m ed.

The possib ility of setting the threshold individually for each channelextends th is m ethod so that it becom es a m ore general W indowTrigger: in order to trigger the input pulse am plitude m ust lie w ith inor outs ide a g iven arbitrary w indow.

Pattern Trigger has been designed to a llow a choice of the triggerpoint. B y choosing 1L*2H entering , the trigger w ill occur at them om ent the pattern 1L*2H becom es true.


��

�� In the case o f Q ua lified T riggers (F ig . 8–16), a s igna l’s trans itionabove or be low a g iven leve l — its va lida tion — serves as anenab ling (qua lifying) cond ition fo r a second s igna l tha t is thesource o f the trigger.

T w o Q ua lified T riggers are ava ilab le : S ta te-Q ua lified , w here theam plitude o f the firs t s igna l m ust rem ain in the des ired s ta te un tilthe trigger occurs ; and E dge-Q ua lified , fo r w h ich the va lida tion issu ffic ien t and no add itiona l requ irem ent is p laced on the firs ts igna l (fo r the separa te , Q ua lified F irs t T rigger, see page 8–24).

A Q ua lified T rigger can occur im m edia te ly a fte r the va lida tion orw ith in a se t tim e a fte r it. O r it can occur fo llow ing apredeterm ined tim e de lay or num ber o f po ten tia l trigger events .T he tim e de la y or trigger count is res tarted w ith every va lida tion .

Figure 8–16. State- and Edge-Qualified Trigger Menus (see pages 8–40 and 8–41).

Qualified

B y

Trigger on

A fte r

E dge |S ta te qua lifie r

H as goneA bove |B e low

va lue

W ith in

W aitO ff|T im e < | T im e> | E vts

1 |2 |3 |4 |E xt|E xt10

or E xt5 depend ing on m ode l

|P a tte rn

1 |2 |3 |4 |E xt|E xt10


Qualified

B y

Trigger on

O nly a fte r

1 |2 |3 |4 |E xt|E xt10


|P a tte rn

1 |2 |3 |4 |E xt|E xt10


E dge |S ta te qua lifie r

G oes and

stays

A bove |B e low

va lue

O ff|T im e < | T im e> | E vtsW ith in

W ait


��

Q ualified T riggers o ffe r the cho ice o f genera ting a trigger w hen ase lec ted pa tte rn is p resent o r absent. A s w ith P atte rn T rigger,the pa tte rn is de fined as a log ica l A N D com bination o f triggers ta tes tha t a re h igh or low : h igh w hen a tr igger source is g rea terthan the se lec ted trigger leve l; low w hen it is less . For exam ple ,a pa tte rn m ight be de fined as presen t w hen the tr igger s ta tes fo rC hanne ls 1 and 2 are h igh and E X T is low . If an y one o f thesecond itions is no t m et, the pa tte rn s ta te is cons idered absent.

Q ua lified T riggers a llow an add itiona l qua lifica tion once the

se lec ted pa tte rn s ta te occurs . For exam ple : “w a it fo r 10 ns up to

20 s , trigger on C H 1 to the 99 999 999 th event.” T he pa tte rn is

used to qua lify the trigger w ithout ac tua lly genera ting it.

T riggering w ill occur w hen another s igna l, the trigger source ,m eets its trigger cond ition w h ile the pa tte rn is p resent. T he

trigger source itse lf is no t a llow ed in the pa tte rn .

�� T yp ica l app lica tions can be found w herever tim e v io la tions occur,

such as in m icro-processor debugg ing, o r te lecom m unica tions.

�� S ta te-Q ua lified T rigger w ith W ait (F ig . 8–17) is de term ined by the

param eters o f T im e or the num ber o f E vents :

� Time determines a delay from the start of the desired pattern. After thedelay (timeout) and while the pattern is present, a trigger can occur.The timing for the delay is restarted when the selected pattern begins.

� Events determines a minimum number of events of the trigger source.An event is generated when a trigger source meets its triggerconditions. On the selected event of the trigger source and while thepattern is present, a trigger can occur. The count is initialized andstarted whenever the selected pattern begins, and continues while thepattern remains. When the selected count is reached, the triggeroccurs.

This example shows a State-Qualified-with-time-Wait trigger: positive slope, 2 ns delay,“goes and stays Above” �24 mV.


��

Figure 8–17. State-Qualified by Wait: Trigger after timeout. The broken upward-pointing arrowsindicate potential triggers, while the bold arrows show where the actual triggers occurs.

A s the above figure illus tra tes , a tr igger is genera ted on a ris ingedge w henever the patte rn is asserted (pa tte rn present) and the

w ait tim eout has exp ired . T he tim eout is ac tiva ted or d isab led

once the patte rn is asserted or absent, respective ly.

This example shows an Edge-Qualified-with-event Wait trigger on CH2 (described next page): positive slope, wait of 109 events, level of

2.50 V, and pattern present as indicated.

Generated TriggerW ait


Trigger can occur

Qualifier: Pattern Present

W ait


��

�� Like its State-Q ualified equivalent, Edge-Q ualified w ith W ait(F ig. 8–18) is conditioned by either T im e or Events:

� Time determines a delay from the start of the desired pattern. Afterthe delay (timeout) and before the end of the pattern, a trigger canoccur. The timing for the delay is restarted when the selectedpattern begins.

� Events determines a minimum number of events for the triggersource. An event is generated when a trigger source meets itstrigger conditions. A trigger can occur on the selected event of thetrigger source and before the end of the pattern. The count isinitialized and started whenever the selected pattern begins. Itcontinues while the pattern remains. When the selected count isreached, the trigger occurs.

Figure 8–18. Edge-Qualified by Wait: Trigger after timeout. The broken upward-

pointing arrows indicate potential triggers, while the bold ones show wherethe actual trigger occurs.

�� Qualified First Trigger (Fig. 8–19) is similar to the Qualified Triggers,and presents exactly the same menus (see page 8–44). Qualified First is

S elected

T im e

S e lected

T im e


Qualifier: Pattern Present

Trigger can occur

Generated Trigger


��

intended to be used exclusively in Sequence Mode to speed up thetrigger rate. With Qualified First, a single valid trigger is sufficient toacquire a full sequence. Other than in Sequence Mode, Qualified Firstis identical to the Qualified Triggers.

Figure 8–19. Qualified First Trigger Menus (see page 8–44).

�� In Data Storage, the index pulse can be defined as the qualifiersignal and the servo gate signal as the trigger source.

Qual First

B y

Trigger on

A fte r

E dge, S ta te qua lifie r

H as goneA bove, B e low

va lue

W ith in

W aitO ff, T im e < , T im e>, E vts

1 , 2 , 3 , 4 , E xt, E xt10 ,

P atte rn

1 , 2 , 3 , 4 , E xt, E xt10


��

Figure 20. Comparing Qualified (top) and Qualified First (bottom) Triggers. Whereas the (Edge-)Qualified Trigger requires that each of the segments be “qualified” by a valid condition in Sequence

Mode, Qualified First Trigger needs only a single valid condition to qualify a full sequence ofsegments. Note that the inter-segment deadtime (DT) is much shorter with Qualified First, which is

used only in Sequence Mode.

This example shows Qualified First Trigger.

D T

Qualifier

S egm ent 1D T

Trigger

S egm ent 2 S egm ent N

D T

Qualifier

S egm ent 1

Trigger

S egm ent 2 S egm ent ND T

(Edge-)Qualified Trigger

Qualified First Trigger


��

�� A spec ia l k ind o f E dge-Q ualified T rigger, T V T rigger (F ig . 8–21)a llow s s tab le tr iggering on s tandard or user-defined com pos itev ideo s igna ls , on a spec ific line o f a num erica lly odd or evenfie ld . T V T rigger can be used on P A L, S E C A M , or N T S Csystem s.

A com pos ite v ideo s igna l on the trigger input is ana lyzed toprov ide a s igna l fo r the beg inn ing o f the chosen fie ld — “an y”,“odd” o r “even” — and fo r a s igna l a t the beg inn ing o f each line .T he fie ld s igna l p rovides the s ta rting trans ition , and thebeg inn ings o f line pu lses are counted to a llow the fina l trigger onthe chosen line . E ach fie ld , the num ber o f fie lds , the fie ld ra te ,in te r lace fac tor, and num ber o f lines per p ic tu re m ust bespec ified , a lthough there are s tandard se ttings fo r the m ostcom m on types o f T V s igna ls . T V T rigger can a lso func tion in as im p le any-line m ode.

Figure 8–21. TV Trigger Menus (see page 8–39 ).

TV

TV s igna l on

# o f fie lds

TV type S tandard , C ustom

1, 2 , 4 , 8

1 , 2 , 3 , 4 , E xt, E xt 10 ,

o r E xt5 depend ing on m ode l

as: 625 /50 /2 :1 , 525 /60 /2 :1

(S tandard)

as: L ine# , H z,

In te rlac ing# :#

(C ustom )

T rigger on L ine# , F ie ld# , any


��

This example TV Trigger shows a trigger on Line 338 of an even field ofa PAL/SECAM signal on CH 1. The “25” in parentheses is the numberof the line selected in Field 1.

��

� Because most TV systems have more than two fields, the enhanced field-countingcapability (FIELDLOCK) allows the oscilloscope to trigger consistently on achosen line within a field of the signal. The field-numbering system is relative, inthat the oscilloscope cannot distinguish between fields 1, 3, 5, or 7 (or 2, 4, 6, or 8)in an absolute way.

� For each of the characteristics the following remarks apply:� 625/50/2:1 (PAL and SECAM systems)

This setting should be used for most of the standard 50-field signals. Thelines may be selected in the range 1 to 626 where line 626 is identical to line1.Number of fields: “4” is most useful for color PAL signals; “8” for SECAMsignals.

� 525/60/2:1 (NTSC systems)This setting should be used for standard 60-field NTSC signals. The linescan be selected in the range 1 to 1051, where line 1051 is identical to line 1.Number of fields: “4” is most useful for US-type NTSC systems.

� ?/50/?, ?/60/?In order to allow maximum flexibility, no line-counting convention is used.The line count should be thought of as a line-synchronizing pulse count. Itincludes the transitions of the equalizing pulses. For certain extreme cases,the field transition recognition will no longer work, and only the “any line”mode will be available.

� The enhanced field-counting capability cannot be used for RIS acquisitions.� Composite video signals must have negative-going synch to be decoded correctly.


��

�� D ropout T rigger (F ig . 8–22 ) prov ides tr iggering w henever the

s igna l d isappears fo r a se t period o f tim e. T he trigger isgenera ted a t the end o f the tim e-out period fo llow ing the “las t”

trigger-source trans ition , as show n in the figure on the next page(F ig . 8–23). T im e-outs o f be tw een 25 ns and 20 s (2 ns and 20 s

fo r the LC564, LC584, AND LC684 SERIES) can be se lec ted .

Figure 8–22. Dropout Trigger Menus (see page 8–42)

�� Dropout T rigger is useful for detecting interruptions in data stream ssuch as network hang-ups and m icroprocessor crashes. A typicalapplication is on the last ‘norm al’ interval of a signal that hasdisappeared com pletely. This is essentially a single-shot application,usually w ith a pre-trigger delay. R IS acquisition is not useful herebecause the tim ing of the trigger tim eout is insufficiently correlated tothe input channel signals.

Dropout

Trigger a fte r

tim eout if no edge

occurs on

W ith s lope

W ith in T im e

P ositive , N egative

1 , 2 , 3 , 4 , E xt, E xt10 ,

o r E xt5 depend ing on

m ode l


��

Figure 8–23. Dropout Trigger: occurs when the time-out has expired. The bold upward-pointing arrows show wherethe trigger occurs.

This Dropout Trigger example shows a waittime-out of 25 ns.

Generated Trigger

Trigger Source

Trigger can occurW ait

T im e-ou tW ait

T im e-ou t


��

R unt

T rigger on

C oup ling

W ithLeve l: upper leve l,

low er leve l


1, 2 , 3 , 4 , E xt, E xt5

W id th : run t <= , run t >=

E dge: N egative , P ositive

T he R unt T rigger (F ig . 8–24 ) is p rogram m ed to occur w hen apu lse c rosses a firs t th resho ld line and fa ils to c ross a secondthresho ld line be fore re -cross ing the firs t (F ig . 8–25). Y ou can

se lec t bo th th resho lds w ith in a range o f 600 ps to 20 s . O therdefin ing cond itions fo r th is trigger a re the edge (triggers on the

s lope oppos ite to tha t se lec ted) and the run t w id th .

Figure 8–24. Runt Trigger Menus (see page 8–45).

�� Runt T rigger is particularly helpful for detecting m eta-stableconditions in dig ital design.

��AAVVAAIILLAABBLLEE OONNLLYYOONN LLCC556644,, LLCC558844,, AANNDDLLCC668844 SSEERRIIEESS


��

Figure 8–25. Runt Trigger: triggers when a pulse crosses the first threshold but not the second beforere-crossing the first — marked by the bold, upward-pointing arrows.

This example sows a positive edge (“Neg” was selected to obtainthis), the difference between the two threshold levels (“veto”), and the

runt width.

Trigger Source

Generated Trigger (Positive Slope)

Generated Trigger (Negative Slope)

U pper Thresho ld Leve l

Low er Thresho ld Leve l


��

S lew R ate T rigger (F ig . 8–26) ac tiva tes a trigger w hen the ris ingor fa lling edge o f a pu lse c rosses tw o th resho ld leve ls : an upperand a low er leve l (F ig . 8–27). T he pu lse edge m ust c ross thethresho lds fas ter o r s low er than a se lec ted period o f tim e. Youcan se lec t bo th th resho lds w ith in a range o f 600 ps to 20 s .

Figure 8–26. Slew Rate Trigger Menus (see page 8–46)

�� S lew R ate T rigger is usefu l fo r m easuring rise tim e or fa lltim e ind ig ita l des ign , m in im iz ing re flec tions .

S lew R ate

T rigger on

C oup ling

W ithdV : upper leve l, low er

leve l


1, 2 , 3 , 4 , E xt, E xt5

dT : dT <= , dT >=

S lope: N egative , P ositive

��

AAVVAAIILLAABBLLEE OONNLLYY OONNLLCC556644,, LLCC558844,, AANNDD LLCC668844SSEERRIIEESS


��

Figure 8–27. Slew Rate Trigger: occurs when a rising or falling edge crosses two thresholds (dV)outside a selected time range (dT), marked by the bold, upward-pointing arrow.

This Slew Rate example is the same as the Edge Trigger symbol,but shows lower (0.556 V) and upper (188 m) threshold levels,

and a time range (≥ 73.6 ns).

Trigger Source

Generated Trigger

U pper

Thresho ld Leve l

Low er Thresho ld

Leve ldT

dV

dT dT dT


��

��

Press to access selection of:

� Trigger source,� Coupling for each source,� Slope (positive or negative), and� Hold-off by time or events.

��

U se th is to se lec t Edge (for an explanation of Edge Trigger, refer topage 8–3).

��

T his se lec ts the tr igger source .

��

T his se lec ts the tr igger coup ling fo r the curren t source .

��

U se th is to p lace the tr igger po in t on the Pos-itive or Neg-a tives lope o f the se lec ted source . LC564, LC584, AND LC684 SERIESONLY: T h is m enu a lso o ffe rs Window, w h ich a llow s tr iggeringw henever the input s igna l ex its a spec ified vo ltage w indow (re fe rto previous page). W hen th is is se lec ted, a “w indow s ize” m enubecom es ava ilab le , w h ich a llow s the w indow to be definedaround a tr igger leve l se t w ith the LE V E L knob.

��T his a llow s you to d isab le the osc illoscope 's trigger c ircu it fo r adefinab le period o f tim e or num ber o f events afte r a tr igger even toccurs . T he ho ld -o ff can be de fined as a period o f Time o r anum ber o f Evts (events a re changes in the inpu t s igna l tha tsa tis fy tr igger cond itions). T he m enu knob is used to vary the“ho ldo ff” va lue . T im e va lues in the range 10 ns to 20 s , o r 2 ns to20 s fo r the LC564, LC584, AND LC684 SERIES� m ay be en tered .E vent counts in the range 1 to 99 999 999 are a llow ed.


��

��

Press to access the various SMART Trigger types:

� Glitch (see page 8-36)

� Exclusion (see page 8-36)

� Interval (see page 8–38)

� TV (see page 8–39)

� State- and Edge-Qualified (see pages 8–40, 8–41)

� Dropout (see page 8–42)

� Pattern (see page 8-43)

� Qual First (see page 8-44)

� Runt — LC564, LC584, AND LC 684 SERIES (see page 8–45)

� Slew Rate — LC564, LC584, AND LC684 SERIES (see page 8–46).

��

U se th is to se lec t SMART.

��

T his prim ary m enu accesses the S M A R T T R IG G E R m enu groupfor choos ing the type o f S M A R T T rigger requ ired from the “type”secondary m enu. D escrip tions o f the “type” and o ther assoc ia tedS M A R T m enu se lec tions s tart next page.


��

��

��

Use this to select Glitch (for an explanation of G litch Trigger, refer topage 8–9).

� Exclusion Trigger is also set using these m enus — refer topage 8–11.

�� Use this to select the trigger source.

��

Use this to select the trigger coupling. HF coupling is not available.

��

Use this to define the test on e ither Pos-itive or Neg-ative pulses.

��≤

On instructs the instrum ent to trigger if the pulse is less than or equalto the value defined here. The value can be adjusted w ith theassociated m enu knob, while the test can be turned on or off bypressing the m enu button, and used in com bination w ith “w idth ≥”.You can enter w idth values in the range 2.5 ns to 20 s (600 ps to20 s for the LC564, LC584, AND LC684 SERIES�).

��≥

On instructs the instrum ent to trigger if the pulse is greater than orequal to the value defined here. The value can be set using theassociated m enu knob. The test can be turned on or off w ith them enu button, and used in com bination w ith “w idth ≤”. The two w idthlim its are com bined to target g litches with in (“&”) a certain range ifthe “w idth ≤” value is greater than the “w idth ≥” value. “O R” indicatesthat glitches above or below th is range w ill be targeted. W idth valuesin the range 2.5 ns to 20 s (600 ps to 20 s for the LC564, LC584, ANDLC684 SERIES ) can be entered.


��

��

W hen Pattern is selected from “trigger on” in G litch m ode (and alsoin Interval m ode — see next page), the instrum ent triggers on thelogic AND of up to five sources.

��

Use this to select Glitch (for an explanation of G litch Trigger, refer topage 8–9).

��

Use this to select Pattern.

��

Use this to select pattern Present or Absent.

��≤

Use this to trigger if the pattern is present or absent for less than orequal to the tim e value defined here. The value can be adjusted withthe associated m enu knob, and the test com m uted to “≥” by pressingthe corresponding m enu button. You can enter w idth values in therange 2.5 ns to 20 s (600 ps to 20 s for the LC564, LC584, AND LC684SERIES ).

��≥

To trigger if the pattern is present or absent for greater than or equalto the tim e value defined here. The value can be adjusted, and thetest com m uted to “≤�” as per “w idth ≤�”. You can enter w idth valuesin the range 2.5 ns to 20 s (600 ps to 20 s for the LC564, LC584, ANDLC684 SERIES ).


��

��

��

Use this to select Interval (for an explanation of Interval Trigger,refer to page 8–12).

��

Use this to select the trigger source. W hen Pattern is selected, theinstrum ent triggers on the logic AND of up to five sources, anddisplays m enus as in G litch-Pattern m ode (see previous page).

��

Use this to select the trigger coupling. HF coupling is not available.

��

Use this to define the interval between two adjacent Pos-itive orNeg-ative edges.

��≤

Set th is to trigger if the interval is less than or equal to the valuedefined here, which can be adjusted using the associated knob. Thetest can be turned on or off w ith the corresponding m enu button, andcan be used in com bination w ith the “interval ≥” test. You can enterinterval values in the range 10 ns to 20 s (2 ns to 20 s for the LC564,LC584, AND LC684 SERIES ).

��≥

Set th is to trigger if the interval is greater than or equal to the valuedefined here, which can be adjusted using the associated m enuknob The test can be turned on or off using the corresponding m enubutton, and can be used in com bination with the “interval ≤” test. Thetwo interval lim its are com bined to select intervals w ith in (“&”) arange if the “interval ≤” value is greater than the “interval ≥” value.“O R” they can be com bined to select in tervals on e ither side of thisrange. You can enter in terval values in the range 10 ns to 20 s (2 nsto 20 s for the LC564, LC584, AND LC684 SERIES�).


��

��

��

Use this to select TV (for an explanation of TV Trigger, refer to page8–26).

��

Use this to select the trigger source.

��

Use this to define the field num ber: odd or even.

��

Use this to select Standard or Custom TV decoding.

��

W hen Standard is chosen, this selects “625/50/2:1” (PAL SEC AM )or “525/60/2:1” (NTSC) standards.

W hen Custom is selected, this specifies the num ber of lines andcycles, and setting the interlacing factor for non-standard TV signals.

��

Use this to select the line and field on which to trigger. W hen it is notim portant that a line be defined (done using the lower m enu knob)“F ield” changes to “any” to allow triggering on an unknown line.


��

��

��

Use this to select Qualified (for an explanation of State-Q ualifiedTrigger, refer to page 8–21).

��

Use this to select State.

��

Use this to select the trigger source. O ther conditions for this source,such as slope and hold-off, m ay be set up using Edge Trigger (seepage 8–34).

��

Use this to select the qualifier source. O ther conditions for thissource, such as slope and hold-off, m ay be set up using EdgeTrigger (see page 8–34). Selecting Pattern as the qualifier sourceoffers the choice of pattern “Present” or “Absent” in the m enu below.

��

Use this to select the qualifier threshold by m eans of the associatedknob, and using the m enu button to select whether the qualifiersignal w ill be valid Above or Below that threshold. Selecting Patternas the qualifier source in the m enu above offers the choice of pattern“Present” or “Absent.”

��

Use this to specify the tim e lim it (“w ithin” “T<”) for accepting thetrigger event. A lternatively, to specify how m uch tim e (“wait” “T>”) orhow m any trigger events (“wait” “Evs”) should be a llowed before theacquisition is taken on the next trigger event. The qualifier signalm ust rem ain valid until the final trigger has been received. The tim evalue can be chosen in the range 10 ns–20 s (2 ns to 20 s for theLC564, LC584, AND LC684 SERIES ). The trigger event count can bechosen in the range 1 to 99 999 999.


��

��

��

Use this to select the Qualified trigger type (for an explanation ofEdge-Q ualified Trigger, refer to page 8–23).

��

Use this to select Edge.

��


��

Use this to select the qualifier source. O ther conditions for thissource, such as slope and hold-off, m ay be set up using EdgeTrigger (see page 8–34). Selecting Pattern as the qualifier sourceoffers the choice of pattern “Present” or “Absent” in the m enu below.

��

Use this to adjust the qualifier threshold and determ ine whether thequalifier signal is valid once it “has gone” above or below thatthreshold. Selecting Pattern as the qualifier source in the m enuabove offers the choice of pattern “Present” or “Absent.”

��

Use this to specify the tim e lim it (“w ithin” “T<”) for accepting thetrigger event. O r, use it to specify the delay in tim e (“wait” “T>”) ornum ber of trigger events (“wait” “Evs”) after a valid transition hasoccurred. A trigger can only be accepted after this delay. Anysubsequent qualifier event restarts this count. The tim e value can bechosen in the range 10 ns to 20 s (2 ns to 20 s for the LC564, LC584,AND LC684 SERIES). The trigger event count can be chosen in therange 1 to 99 999 999.


��

��

��

Use this to select Dropout (for an explanation of Dropout T rigger,refer to page 8–42).

��

��

Use this to select the trigger source .

��

Use this to define whether the m easurem ent starts on a Positive orNegative slope of the trigger signal.

��

For defining the tim e-out value in the range 25 ns to 20 s (2 ns to20 s for the LC564, LC584, AND LC684 SERIES).


��

��

��

Use this to select Pattern (for an explanation of Pattern Trigger, referto page 8–17).

��

Use this to select Entering for the instrum ent to trigger when thepattern starts being true , and Exiting for triggering when it stopsbeing true .

��

Use this to select the channel to be m odified using the lower m enus’corresponding m enu buttons.

��

Use this to select the desired coupling. HF coupling is not available.

��

This is for m odifying level values, using the associated knob and thecorresponding m enu button to choose L (low), H (high), or X (don'tcare).

��

Use this to d isable the trigger circuit for a definable period of tim e ornum ber of events after a trigger event (a change in the input signalthat satisfies the trigger conditions). W hen not turned off, holdoff canbe defined as a period of Time or a num ber of Evts (events). Usethe associated m enu knob to vary the “holdoff” value. You can entertim e holdoff values in the range 10 ns to 20 s (2 ns to 20 s for theLC564, LC584A, and LC684). Event counts in the range 1 to 99 999999 are a llowed.


��

��

��

Use this to select Qual First (for an explanation of Q ualified FirstTrigger, refer to page 8–24).

��

Use this to select Edge or State.

��


��

Use this to select the qualifier source. O ther conditions for thissource, such as slope and hold-off, m ay be set up using EdgeTrigger (see page 8–34). Pattern selected as the qualifier sourcedeterm ines whether the pattern should be “Present” or “Absent.”

��

To adjust the qualifier threshold and determ ine whether the qualifiersignal is valid once it “has gone” above or below that threshold.Selecting Pattern as the qualifier source in the m enu above offersthe choice of pattern “Present” or “Absent.”

��

To specify the tim e lim it (“wait” “T<”) for accepting the trigger event.O r, to specify the delay in tim e (“wait” T>) or num ber of trigger events(“wait” Evs) after a valid transition has occurred. A trigger can onlybe accepted after this delay. Any subsequent qualifier event restartsthis count. You can choose a tim e value in the range 10 ns to20 s,and a trigger event count in the range 1 to 99 999 999.


��

�� LLCC556644,, LLCC558844, AND LC684 SSEERRIIEESS OONNLLYY

��To select Runt (for an explanation of Runt T rigger, refer to page8–30).

��Use this to select the trigger source.

��Use this to select the trigger coupling. HF coupling is not available.

��Use this to select and set the three defining conditions for the RuntTrigger:

� W hen Level is selected (not shown at left), these m enus appear:

��Use th is to set the level of the upper threshold through whichthe runt m ust pass.

��U se th is to se t the leve l o f the low er th resho ld th rough w h ichthe run t m ust pass .

� W hen Width is selected, the m enus shown at left appear. The twowidth lim its can be com bined to select runt pulses within (“&” w illappear in the second m enu) a certain range if the “runt ≤” value isgreater than the “runt ≥” value. O r they can be com bined to selectrunts outside th is range (“O R” w ill appear).

��≤W hen On is selected, there w ill be a trigger if the runt pulsew idth is less than or equal to the defined value (600 ps to 20 s),adjusted with the associated m enu knob. The test is be turnedon or off using the m enu button, in com bination with “runt ≥”.

��≥W hen On is selected, there will be a trigger if the runt pulse widthis greater than or equal to the defined value (600 ps to 20 s),adjusted with the associated m enu knob. This condition can beturned on or off by m eans of the m enu button, and used incom bination with “runt ≤”.

� W hen Edge is selected (not shown), the “at end of” m enu appears,allow ing the trigger to be defined as occurring at the end of a“Negative” or a “Positive” runt slope.


��

�� LLCC556644,, LLCC558844, AND LC684 SSEERRIIEESS OONNLLYY

��Use this to select Slew Rate (for an explanation of S lew RateTrigger, refer to page 8–32).

��Use this to select the trigger source.

��Use this to select the trigger coupling.

��Use this to select and set the three defining conditions for the S lewRate Trigger:

� W hen dV is selected (not shown at left), the following m enus appear:

��Use this to select the level of the upper threshold.

��Use this to select the level of the lower threshold.

� W hen dT is selected, these m enus appear below:

��≤W hen On is selected, there w ill be a trigger if the tim e is lessthan or equal to the defined value (600 ps to 20 s), adjusted withthe associated m enu knob. This condition can be turned on oroff using the m enu button, in com bination with “dT ≥.”

��≥W hen On is selected, there w ill be a trigger if the tim e is greaterthan or equal to the defined value (600 ps to 20 s), adjustedusing the associated m enu knob. This condition can be turnedon or off w ith the m enu button and used in com bination with“dT ≤”. They can be com bined to select pulses within (“&”) acertain range if the “dT≤” value is greater than the “dT≥” value.“O R” they can be com bined to select pulses on e ither side ofthis range.

� W hen “Slope” is selected (not shown at left), the “w ith s lope” m enuappears, allow ing the slope to be defined as “Negative” or “Positive.”

# # #


� ��

��

A wide range of Zoom and Mathematical processingfunctions (detailed in the next chapter) can be performed onacquired waveforms with the controls described here.

Four processed tracesare available for norm alzoom ing or for waveformm athem atics. Any one oftraces A, B, C or D can beset up to zoom another ofthese, or another traceacquired on any channelor stored in one of the fourreference m em ories M 1–M 4. Trace A, for exam ple,could be set up to zoomTrace B, C , or D , but notitself. The D isplayedTrace label at the left ofthe screen indicates thesource.

T h e TRACEON/OFF buttons display the corresponding trace A, B, C , or D .

W hen a trace is switched on, the PO SIT IO N and ZO O M knobs andthe RESET button (described next page) w ill then be attributed tothis, the active trace.

T he SELECT ABCD bu tton ass igns the contro ls to the

active trace fo r ad jus tm ent because on ly one trace can bem odified a t a tim e. P ressing this button activates the next trace inthe A to D sequence.

T he four ZO O M + M A T H knobs ad jus t the horizonta l and vertica lpos itions and expans ion fac tors o f the zoom ed trace…


��

T he POSITION knob repos itions zoom ed traces

horizonta lly . If the source o f the expanded w aveform is d isp layed,

an in tens ified reg ion correspond ing to the area o f expans ion isshow n.

W hereas the vertica lly repos itions the ac tive trace .

T he knob horizonta lly expands or contrac ts the ac tive

trace . If the source o f the zoom ed trace is a lso d isp layed, it w illshow an in tens ified reg ion correspond ing to the area o fexpans ion .

W hile the vertica lly expands or contrac ts the ac tive

trace .

T he RESET bu tton rese ts the vertica l and horizonta l

P O S IT IO N and ZO O M .

F ina lly, the m enu-entry bu tton accesses the zoom ,

m ath , and sequence segm ent fea tures . S ee next chapter fo rde ta ils .

# # #


��

��

You can zoom several traces from a single waveform toobtain precise timing measurements.For ins tance, on a w aveform com posed o f tw o pu lses separa tedby a long de lay, T race A cou ld be m ade a zoom o f the firs t pu lse ,and T race B a zoom o f the second.

T he com bination o f long m em ory and zoom capab ility a llow sextrem ely accura te m easurem ents o f tim e in te rva ls . T hus thetim e reso lu tion on the v iew ed trace can be s ign ifican tly im proved.

For exam ple , choos ing 50 000 po in ts per channe l on a tim ebaseof 0 .1 m s/d iv , traces can be expanded to as m uch as 50 ns /d iv— a fac tor o f 2000. U s ing R e la tive T im e cursors (see C hapter14), th is m eans tha t a de lay o f 500 µs cou ld be m easured w ith areso lu tion as h igh as 0 .5 ns . E ven w ith as m any as e igh t m illionpo in ts acqu ired , success ive zoom ing can be done until there areon ly a few po in ts on the screen.

�� W ith M ulti-Zoom , the zoom ed reg ion o f the w aveform can bem oved s im u ltaneous ly a long tw o or m ore d iffe ren t traces, o r tw oor m ore reg ions o f the sam e trace .

W hen M ulti-Zoom On is se lec ted from the ZO O M – M A T H m enu(see page 10–8), the horizonta l zoom and pos ition contro ls app lys im u ltaneous ly to a ll d isp layed traces — A , B , C , and D —allow ing s im ila r sec tions o f d iffe ren t traces to be v iew ed a t thesam e tim e. H ow ever, the vertica l contro ls s till ac t on the tracesind iv idua lly (see prev ious chapter). T he h igh ligh ting o f trace titlesin the D isp layed T race labe l ind ica tes an ac tive M ulti-Zoom .

�� W hen Trace A, B, C , or D is defined as a m athem atical functionrather than as a sim ple zoom (see next section), the zoom controlsrem ain operative; that is, it is not necessary to define another traceas a zoom of the m ath function. In order to view the entirem athem atical function, sim ply cancel any expansion or positionchange by pressing RESET.


��

��

A wide range of standard or optional mathematical andwaveform processing functions is available on LC Seriesoscilloscopes. Not all functions are described here. Thosesuch as Histogram, Trend, and Correlate are described intheir dedicated Operator’s Manuals, if these functions areinstalled in the oscilloscope.T he scope ’s s tandard w aveform m athem atics func tions cons is to f w aveform negation , identity, add ition , subtrac tion ,m u ltip lica tion and d iv is ion , sum m ed averag ing o f up to 1000w aveform s and the (s in x )/x in te rpo la tion func tion .

T he advanced w aveform process ing fea tures inc lude thefo llow ing :

� C ontinuous A verag ing (m enus on page 10–10)

� S um m ed A verag ing o f up to 1 000 000 w aveform s (m enuson 10–10)

� E nhanced R eso lu tion by up to 3 b its w ith filte ring (m enus onpage10–11)

� E x trem a — enve lope o f m any w aveform s (m enus on page10–12)

� Fas t Fourie r T ransform , inc lud ing FFT averag ing (m enus onpages10–13 and 10–14)

� M athem atica l Functions such as In tegra l, D eriva tive ,Logarithm , E xponentia l, S quare , and S quare R oot (m enus onpage10–15)

�� T h is is the repeated add ition (w ith unequa l w e igh t) o f success ivesource w aveform s. It is particu la rly usefu l fo r reduc ing no ise ons igna ls tha t d rift very s low ly in tim e or am plitude.

H ow ever, the s ta tis tics o f a continuous average tend to be w orsethan those from a sum m ed average (see next page) on the sam enum ber o f sw eeps. T h is is because the m ost recently acqu iredw aveform has m ore w e ight than a ll p rev ious ly acqu ired ones: thecontinuous average is dom inated by the s ta tis tica l fluc tua tions o fthe m ost recently acqu ired .

Descriptions of the Setupmenu’s zoom, math, andwaveform processingfunctions start on page10–6. Averaging andExtrema are outlined onthis and following pages.For details on EnhancedResolution filtering seeAppendix B.How to set up FFT (FastFourier Transform) isexplained at theconclusion of thischapter. FFT theory andpractice are described inAppendix C.


��

T he w e igh t o f ‘o ld ’ w aveform s in the continuous average tends tozero (fo llow ing an exponentia l ru le ) a t a ra te tha t decreases asthe w e igh t increases.

�� S um m ed A verag ing is the repeated add ition (w ith equa l w e ight)o f success ive source w aveform records . If a s tab le trigger isava ilab le , the resu lting average has a random no ise com ponentlow er than tha t o f a s ing le-shot record .

W hen the m ax im um num ber o f sw eeps is reached, theaverag ing process s tops. A n even la rger num ber can beaccum ula ted s im ply by chang ing the num ber in the S E T U P “fo r”m enu. H ow ever, the o ther param eters m ust be le ft unchanged ore lse a new averag ing ca lcu la tion w ill be s tarted .

You m ay in terrup t the process by chang ing the trigger m ode fromN O R M to S T O P or by tu rn ing o ff the ac tive trace, us ing therespective buttons. A verag ing w ill be resum ed w hen you do theoppos ite . T he accum ula ted average is reset w hen you push theC LE A R S W E E P S button or change an acqu is ition param etersuch as input ga in , o ffse t, coup ling , trigger cond ition , tim ebase,or bandw id th lim it. T he num ber o f curren t averaged w aveform sof the function or its expans ion is show n in the D isp layed T racelabe l.

W hen you se lec t sum m ed averag ing , the d isp lay is updated a t areduced ra te — about once every 1 .5 s — in order to increasethe averag ing speed (po in ts and events per second).

S um m ed averag ing can a lso be done on sequence w aveform s tog ive the average o f the segm ents . It can a lso be app lied to anexpans ion o f a sequence segm ent, g iv ing the segm ent’s averagew aveform over m any sequence acqu is itions .

�� T hese are com puted by a repeated com parison o f success ivesource w aveform records w ith the a lready-accum ula ted ex trem aw aveform , w h ich cons is ts o f a m ax im a (roo f) and a m in im a(floor) record . W henever a g iven da ta po in t o f the new w aveformis g rea ter than the correspond ing m ax im um roof-record va lue , o rless than the correspond ing floor va lue , the new data po in trep laces the o ld . T hus the m ax im um and the m in im um enve lopeof a ll w aveform records is accum ula ted .

R oof and F loor records can be d isp layed ind iv idua lly o r together.


��

W hen the se lec ted m ax im um num ber o f sw eeps is reached, theaccum ula tion s tops. You can in te rrup t the sam e process bychang ing the trigger m ode from N orm al to S topped or by tu rn ingoff the func tion trace . A ccum ula tion w ill con tinue if you do theoppos ite .

You can rese t the curren tly accum ula ted ex trem a w aveform bypush ing the C LE A R S W E E P S button or by chang ing anacqu is ition param eter, such as input ga in , o ffse t, coup ling , triggercond ition , o r the tim ebase or bandw id th lim it. T he num ber o fcurren tly accum ula ted w aveform s is d isp layed in the func tion ’sD isp layed T race Labe l o r tha t o f its zoom expans ion .

W hen the m ax im um num ber o f sw eeps is reached, an evenlarger num ber can be accum ula ted s im p ly by chang ing thenum ber in the S E T U P “fo r” m enu. H ow ever, the o therparam eters m ust be le ft unchanged or e lse the ex trem aca lcu la tion w ill be res tarted .


��

��

You can apply waveform mathematics to any channel orreference memory. Furthermore, any trace of A, B, C, or Dcan be set up as a math function, allowing severalcomputations to be made in sequence.For exam ple : T race A cou ld be se t up as the d iffe rence be tw eenC hanne ls 1 and 2 , T race B as the average o f A , and T race C thein tegra l o f B . T hus the in tegra l o f the averaged d iffe rencebetw een C hanne ls 1 and 2 is d isp layed.

In o rder to avo id s low ing dow n the ins trum ent w ith unw antedcom puta tions , a particu la r m athem atica l func tion is on lycom puted w hen its d isp lay is tu rned on . U s ing the sam e exam pleas above, how ever, it w ou ld be su ffic ien t to d isp lay T race Ca lone because the ins trum ent know s it m ust com pute A and Bbefore C .

W aveform process ing can a lso take tim e w hen m any data po in tsare invo lved. T h is de lay can be cu t by lim iting the num ber o f da tapo in ts used in the com puta tion . T o do th is , the ins trum ent w illp rocess the en tire w aveform by tak ing every N

th po in t, w here N

depends on the tim ebase and the des ired m ax im um num ber o fpo in ts . T he firs t po in t taken is a lw ays the da ta va lue a t the le ft-hand edge o f the screen.

�� Zoom and m ath functions on Traces A, B, C , D , and ReferenceM em ories M 1, M 2, M 3, and M 4 use the instrum ent’s systemm em ory, which is dynam ically allocated to each trace as required.W hen you achieve m ore acquisition m em ory by com bining channels,a single long trace can consum e all the reference m em ory or zoomand m ath trace capacity in the instrum ent. W hen this happens, anon-screen m essage will warn you of the possibility of accidentallystoring a new trace to a reference m em ory already in use. R efer toC hapter 7 .

�� A processing title for each displayed trace will beshown in the Displayed Trace Label. If the title is missing,the desired processing cannot be done, and the contentsof the trace remain unchanged.


��

��

Press to configure any of the four traces and toexecute any zoom or math function using the “ZOOM + MATH”menus.Any trace and function can be chained to another trace and function(not all functions shown m ay be available on your oscilloscope). TraceA, for exam ple, could be m ade an average of CH 1, Trace B an FFT ofA, and Trace C a zoom of B. All traces can be viewed sim ultaneouslyby m eans of the TRACE ON/OFF buttons; and any function can bezoom ed directly.

��Select one of these to redefine a trace and to access the SETUP m enus(described in the rem ainder of this chapter, using Trace A as anexam ple).

��This selection accesses the Multi-Zoom and Auto Scroll functions (seepage 10–8). W ith Multi-Zoom activated, all displayed zoom traces aresim ultaneously controlled by the horizontal POSITION and ZOOMknobs, and by Auto Scroll. W hen Multi-Zoom is not used, only the activezoom trace is controlled. Auto Scroll displays the captured signal with azoom expansion that autom atically m oves across the screen. You canselect the scroll speed, scroll through the acquired waveform and pauseon any feature.

��W hen a trace with a zoom of a sequence-m ode waveform isselected, the “Selected” m enu becom es accessible. Press thecorresponding m enu button to toggle the selection between displayof a single, specific “Segm ent” and “A ll Segm ents.” W ith “Segm ent”selected, the associated knob can be used to choose specificsegm ents.

��…This is for selecting the m axim um num ber of points for all m athoperations. A low num ber increases com putation speed.

LC X X X -O M -E R ev K IS S U E D : N ovem ber 1999 ��

��

�� T his appears w hen “REDEFINE A” (for exam ple) is selected fromthe “ZO O M + M ATH” m enus.

��

This is for toggling between No (Zoom only) and Yes (M athfunctions) setups.

��

This selects the source trace to be zoom ed.


��

�� This appears when “ZO O M and Auto-Scroll” is selected from theZO O M + M ATH m enu group. M ULTI-ZO O M unifies the control of allzoom traces, while AUTO -SCRO LL m oves the zoom trace (ortraces) across the referenced trace.

��

W hen Off is selected, only the active zoom trace is controlled. W henOn is selected, all displayed zoom traces (A,B,C ,D) are autom aticallycontrolled at the sam e tim e with Auto Scroll, and m anually w ith thehorizontal ZO O M and PO SIT IO N knobs.

��

Use this feature to scroll the zoom trace from right to left. W henactive, the label displays “STO P (PLAYING ): Press to stop.”

��

Use this feature to scroll the zoom trace from left to right. W henactive, the label displays “STO P (REVERSING )”: Press to stop.

��

Use this feature to scro ll by d iv is ions per second or by num ber o fd iv is ions. U se div/s to scro ll con tinuous ly. U se number of divfo r w aveform process ing , espec ia lly P ass/Fa il tes ting . W henprocess ing is com ple ted, the d isp lay w ill be updated by thenum ber-o f-d iv is ions se t.

��

Use this knob to set scroll speed. W hen you are scrolling bydivisions, 10 div w ill step the zoom trace “grid page” by “grid page”across the length of the referenced trace.

��

W hile continuing to scroll, use this button to return to the previousm enus.

�� If you press the standard RETURN button, the waveformwill stop scrolling and the previous menu will be displayed.


��

�� — allows addition, subtraction, m ultiplication and division, as well aschoice of the two operands and the operator. The exam ple on thispage shows a setup of trace A as the sum of Channels 1 and 2.

��

Select Yes to enable the choice of a m ath function.

��

U se th is subm enu to se lec t Arithmetic.

��

U se th is subm enu to se lec t the opera tor.

��

U se th is subm enu to se lec t one o f tw o operand source traces.

��

U se th is subm enu to se lec t the o ther operand source trace .


��

�� This feature� offers Sum m ed (Linear) or Continuous (Exponential)Averaging. Shown here is an exam ple setup of trace A as aSum m ed Average (over 1000 sweeps) of Channel 1. (See also page10–2.)

��


��

Use this subm enu to select a specific m ath function (Average in thiscase).

��

Use this to select Summed or Continuous averaging m ethod.

��

W hen you select Summed averaging, “for… sweeps” lets you specifythe num ber of sweeps. If you select Continuous averaging,however, the sam e m enu item becom es “w ith… weighting,” whichlets you define the weight. The difference between the two choices isthat when Summed is selected the first n sweeps will be taken intoaccount, whereas in Continuous averaging the last sweep will begiven a weight of 1 and the previous result a weight of n in thecalculations.

��

Use this to select the source trace for averaging.


��

�� This lets you select low-pass digital filters that increase the resolutionof the displayed signal at the expense of its bandwidth. (SeeAppendix B for a detailed explanation.)

T hese d ig ita l filte rs w ork very m uch like ana log bandw id th-lim itfilte rs . In S ing le-S hot m ode, they and the sam pling speed a ffec tbandw id th . If h igh bandw id th is needed a t s low tim ebases, youshou ld cons ider averag ing and repetitive sam pling ins tead.

��


��

Use this subm enu to select Enhanced Resolution.

��

Use this subm enu to select the filter that w ill enhance resolution ofthe displayed signal. Enhancem ent is possible from one to three bitsin 0.5-bit steps.

��

Use this to select the source trace for filtering.


��

�� This is used for acquiring a trace envelope over m any acquisitions(see also page 10–3).

��


��

Use this subm enu to select Extrema.

��

Use this subm enu to select either Envelope, Floor, or Roof. F loorshows only the lower, and Roof only the upper part of the envelope.Changing the lim its does not force the analysis to start again.

��

This lets you select the num ber of sweeps.

��

This lets you select the source trace.


��

�� This is used to display the Fast Fourier T ransform (FFT) of a signal

and to view it in the frequency dom ain. (See the final section of thischapter, and Appendix C , for when and how to use FFT .)

��


��

Use this subm enu to select FFT.

��

Use this subm enu to select the FFT’s output form at: Imaginary,Magnitude, Phase, Power Dens-ity, Power Spect-rum , Real orReal + Imag.

��

Use the corresponding m enu button to select the FFT window type,and the associated knob to select AC or DC.

��

Use this to select the source trace.

�� During Fast Fourier Transform computation the FFT sign

is displayed in the lower right-hand corner of the screen.� The computation of FFT on long time-domain records

can take a while.� You can interrupt or cancel the computation at any time

by using any front-panel control.


��

�� This is used for displaying the FFT power averaging of an FFTsource trace. Power averaging is useful for characterizing broadbandnoise or periodic signals w ithout a stable trigger signal. Total power— signal and noise — is m easured at each frequency. The sourcetrace m ust be an FFT function. (See the final section of this chapter,and Appendix C , for when and how to use FFT.)

��


��

Use this subm enu to select FFT AVG.

��

Use this subm enu to select the output form at of the FFT Average:Magnitude, Power Density, or Power Spectrum.

��

Use this to select the num ber of sweeps.

��

Use this to select the FFT source.

�� FFT Average can be reset by pressing CLEARSWEEPS. The number of currently accumulatedwaveforms is then shown in the Displayed Trace field ofthe function or its expansion.


��

�� This gives you access to a variety of M ath display functions.

��


��

Use this subm enu to select Functions.

��

Use this subm enu to select a function type from :

� Absolute value� Derivative� Exp (base e)� Exp 10 (base 10)� Identity� Integral� Log (base e)

� Log 10 (base 10)� Negation� Reciprocal� Sinx/x� Square� Square root

��

This is used to select the signal offset (used to com pensate for anyDC offset in the signal).

��

Use this subm enu to select the source trace.

��

� Square root is computed on the absolute value of the sourcewaveform.

� For logarithmic and exponential functions, the numericalvalue (without units) of the input waveform is used.

� For the integral function, the source waveform may be offsetby an Additive Constant in the range �1016 to �1016 times thevertical unit of the source waveform.


��

�� This deskew feature allows a signal on one channel to beresam pled, and adjusted in tim e relative to a signal on anotherchannel. It is valuable wherever there is the need to com pensate fordifferent lengths of cables, probes or other factors causing tim ingm ism atches.

��


��

Use this subm enu to select Resample.

��

Use this to set the adjustm ent (deskew) that w ill com pensate for thetim ing differences between signals on two channels, using theassociated m enu knob (range = ± 2000 ns).

��



��

�� This is used for selecting a waveform and adjusting a (them ultiplication factor) and b (the additive constant) in the form ula:

(a ∗ waveform ) + b,

where both constants can have values ranging between −1015 and+1015.

��


��

Use this subm enu to select Rescale.

��∗��

Use this to select a or b.

��

The corresponding m enu button for this m enu highlights them antissa, the exponent, or the num ber of digits, while the associatedknob changes the highlighted value.

��



��

��

The FFT (Fast Fourier Transform) converts a time domainwaveform into frequency domain spectra similar to those ofan RF spectrum analyzer display. But unlike the analyzer,which has controls for span and resolution bandwidth, FFTspan is determined by sampling rate, while resolutionbandwidth is inversely proportional to record length.

��Δ� C orrec tly se tting up an FFT s tarts w ith the frequency reso lu tion(Δf). T h is param eter is the spac ing o f sam ples in the frequencydom ain d isp lay. T he Δf is se t by inputting the tim e dura tion o f thetim e dom ain s igna l to the FFT . If an acqu is ition channe l (C hanne l1 , 2 , 3 , o r 4 ) is the source , the w aveform dura tion is the capturetim e: the T IM E /D IV se tting m ultip lied by ten . T he re la tionsh ipbetw een capture tim e and frequency reso lu tion is illus tra ted here .

TIME

CAPTURE TIME= 10 X TIME / DIV

FREQUENCY

AM

PLIT

UD

EA

MPL

ITU

DE

Δ f

FREQUENCYRESOLUTION

ACQUIRED WAVEFORM

FAST FOURIER TRANSFORM (FFT)

Δ f = 1/ CAPTURE TIME


��

S im ila rly, if the source w aveform is a zoom trace, the frequencyreso lu tion is the rec ip roca l o f the d isp layed w aveform ’s dura tion .

�� T he frequency span o f the FFT is ca lled the N yqu is t frequencyand is re la ted to the sam pling frequency o f the tim e dom ainw aveform . If the m ath m em ory s ize , w h ich is se t us ing the “fo rM ath use m ax po in ts ” m enu (see page 10–6), is identica l to thenum ber o f sam ples in the acqu ired w aveform (C hapter 7 ,T IM E B A S E m enus), the span w ill be ha lf the sam pling frequency.B ut if th is “m ax po in ts fo r m ath” num ber is less than the num bero f po in ts , the w aveform and, in tu rn , the FFT span w ill bedec im ated. T he re la tionsh ip be tw een the span o f the FFT andthe sam pling ra te (1 /ΔT ) is illus tra ted here .

TIME

FREQUENCY

AM

PLIT

UD

EA

MPL

ITU

DE

ACQUIRED WAVEFORM

FAST FOURIER TRANSFORM (FFT)

Δ T

FREQUENCY SPAN

SAMPLING PERIOD

FREQUENCY SPAN = K * ( 1/ΔT)


��

T he constant K in the illus tra tion inc ludes the dec im ation fac tordescribed above, as w e ll as au tom atic d isp lay sca ling fac tors .T h is sca ling is requ ired to ensure tha t the FFT ’s horizonta ld isp lay sca le fa lls in to a 1 ,2 , o r 5 fac tor.

In essence, the osc illoscope autom atica lly ad jus ts the span (andhence the FFT trans form s ize) to account fo r the user-en tered“m ax po in ts fo r m ath” and the d isp lay sca ling . In som ecom binations o f these fac tors it a lso ad jus ts the length o f thed isp layed trace .

You can de term ine the span from the D isp layed T race Labe l fo rthe m ath trace conta in ing the FFT . T h is w ill show the horizonta lca lib ra tion in H z/d iv . T he span is a lso exp lic itly show n as theN yqu is t frequency in the in fo rm ation fie ld tha t appears a t thebottom o f the screen w hen the “M A T H S E T U P ” m enus ared isp layed, as show n here .


��

�� T o ach ieve a des ired FFT span, firs t m ake sure tha t the sam plingra te is m ore than tw ice the span des ired . C ontro l the sam plingra te us ing the T IM E /D IV knob and se t the acqu is ition m em oryleng th w ith the “T IM E B A S E ” m enu. T he sam pling ra te can befurther ad jus ted by lim iting the num ber o f po in ts in the “fo r M athuse m ax po in ts ” m enu.

�� S et up the osc illoscope fo r an FFT w ith a span o f 10 M H z and afrequency reso lu tion o f 10 kH z, to ana lyze a continuous, period icw aveform .

1 . T he requ ired frequency reso lu tion dem ands a w aveformdura tion (capture tim e) o f 100 µs . S et the T IM E /D IV to 10 µsto ach ieve the necessary Δf o f 10 kH z.

2 . T o ob ta in the spec ified 10 M H z span, the e ffec tive sam plingra te m ust be >20 M S /s . O n an osc illoscope w ith a sam plingra te o f 500 M S /s , fo r exam ple , the de fau lt m em ory length o f50 000 sam ples and a T IM E /D IV se tting o f 10 µs w ou ld beused to firs t g ive a span o f 250 M H z. N ow , to ob ta in a spanof 10 M H z, the sam pling ra te m ust be reduced. T h is can bedone in tw o w ays:

a) In “T IM E B A S E ”: decrease the num ber o f sam ples bysetting the “R E C O R D U P T O ” m enu to 2500 resu lts in asam pling ra te o f 25 M S /s .

b) W ith “ZO O M + M A T H ”: se t the “fo r M ath use m ax po in ts ”m enu to 2500. T h is w ou ld leave the sam pling ra te a t 500M S /s bu t dec im ate the w aveform data be fore the FFT toreduce the e ffec tive sam pling ra te to 25 M S /s . T h isw ou ld in tu rn resu lt in a span o f 12 .5 M H z, the c losestach ievab le span to >10 M H z.

�� The technique described in b) above is preferredbecause it maintains a high input sampling rate and reducesthe risk of aliasing the acquired data.


��

T he exam ple illus tra ted be low show s how the osc illoscopem ain ta ins the d isp lay fac tor. A sam pling ra te o f 25 M S /s w ou ldresu lt in a fu ll sca le range o f 12 .5 M H z or 1 .25 M H z/d iv . T om ain ta in a d isp lay sca le fac tor o f 1 , 2 , o r 5 , it dec im ates theacqu ired w aveform and ca lcu la tes the FFT us ing a2000-po in t trans form . T h is resu lts in a sca le fac tor o f 2 M H z/d iv .T he d isp lay is truncated a t 6 .25 d iv is ions to re ta in the orig ina lspan o f 12 .5 M H z.

# # #


��

��

The large display reveals the complete picture withadvanced color management. Colors are used to give on-screen objects added depth and distinctness, and to clarifytheir relationships.T he d isp lay is in te lligent as w e ll as pow erfu l. C o lor and in tens ityare m anaged autom atica lly in rea l tim e by a hardw are-supportedsystem tha t has the added advantage o f very low so ftw are-overhead. T races can be d isp layed opaque ly or transparently.O verlapp ing ob jec ts — traces over traces or traces over g rids —are a lw ays v is ib le in transparent m ode (see page 11–3).

S igna ls and the ir re la ted data are co lor assoc ia ted (page 11–2).E ach trace has its ow n ded ica ted co lor and pers is tence datam aps. B acked by 1 M B o f v ideo m em ory, in fin ite and variab lepers is tence d isp lays are autom atica lly co lo r m atched to theparent trace. R e la ted traces and tex t, screen icons, and parent–daughter zoom reg ions are a lso linked by co lor. A s m any as e igh ttraces can be d isp layed a t once, on e igh t separa te grids (page11–12). T he Fu ll S creen function uses the entire screen area tod isp lay traces (page 11–10 ).

T here are s ix p reset co lo r schem es and four persona l co lo rpa le ttes you can cus tom ize (page 11–20), d raw ing on m ore than40 d iffe ren t co lo rs (page 11–3).

T he un ique A na log P ers is tence™ fea ture (see page 11–5) o ffe rsadvantages o f an ana log d isp lay in a d ig ita l osc illoscope. U se o fthe brigh tness leve l o f a s ing le co lo r to denote re la tive s igna lin tens ities is the s tandard P ers is tence m ode. A lso ava ilab le isC o lor G raded P ers is tence (page 11–15), w h ich uses a co lo rspectrum from red th rough v io le t to m ap s igna l in tens ity. B othpers is tence m odes are in fin ite o r variab le w ith decay over tim e.T hey can be chosen from the D IS P LA Y S E T U P m enus (seedescrip tions s ta rting page 11–7 ).


��

��

The Advanced Color Management System ensures that boththe objects and the relationships between them are alwaysclearly visible — even when the objects overlap. Objectsinclude:� Waveforms, including envelopes and intensified regions� Grids� Parameter Measurements� Cursors� Status Information

�� Color m anagem ent of the background plays an im portant role inbringing out the links and differences between displayed objects. Thechoice of background colors has been purposely lim ited to the darkercolors so that displayed objects are m ore clearly defined andrecognizable. The colors of objects that are too close in hue to thechosen background color are autom atically changed so that theseobjects always stand out from the background.

�� The base color of a trace is specified for each color schem e.However, the expanded or zoom ed sections of a trace can be giventheir own colors, so that a single trace m ay have a num ber of colorsat once: its principal color plus those of the expansions.

�� Trace-related text includes pieces of on-screen inform ation thatdescribe m easurem ent param eters, cursors, triggers, waveform s,and channels. A standard text color for all on-screen text exists in thepreset color schem es, or can be chosen for custom palettes.W aveform source descriptions including param eter string,acquisition setup, status screen, and trigger inform ation will be in thetrace color, even when contained in a text string (the rem ainder ofwhich will be in the text color). W aveform descriptor boxes — tracelabels — and the inform ation they contain always take the color oftheir respective trace.

�� M ost m enus are displayed in the text color only. The active triggeredge or trigger condition shows source-related inform ation in thetrace color, as does the trigger icon. But the titles of Channel


��

Coupling m enus are trace-colored, and M ath Setup m enu sourceshave their own color as well.

�� Selection of the Opaque presentation of overlapping waveform splaces one on top of another in norm al, non-transparent layers. Youcan also select the order in which traces appear (see below).

However, when Transparent is chosen and overlap m ixing is used,those areas of the waveform s that overlap will autom atically changecolor while grid intensity rem ains constant. But this contrastenhancem ent m arks the overlapping regions so that they stand out.O verlap m anaged traces always rem ain distinct in relation to otherdisplayed objects and to the background.

�� This is another m echanism for recognizing displayed objects, whichautom atically overlays them on the screen in sequence.

W hen dealing with traces of the sam e type, the forem ost trace isdescribed in the top-left trace label, the next in the second tracelabel, and so on in descending order towards the background andthe bottom of the screen, respectively. You can change this orderwith the CHANNELS TRACE O N/O FF buttons.

W hen different types of traces are displayed, by default they areplaced in ascending order from the grid at the bottom as follows:envelope traces, persistence traces, norm al traces, and cursors.This sequence can also be custom ized.

For extrem a waveform s the sequence is followed by a repeatedscanning of norm al traces, ensuring that they are always viewedwithin extrem a, regardless of display order. Thus each trace is visiblewithin its envelope, persistence, or Pass/Fail m ask; grid lines neverhide trace features; and cursors are always visible.

�� Any color can be chosen as “neutral” in the four user color schem es;a neutral color is designated by default in each of the six presetschem es. W hen the “M easure G ate” function is switched on, thisdesignated neutral color autom atically relegates display objects oflim ited interest to the area outside the m easurem ent-gate region(see page 11–21), thus indirectly highlighting the area of greatestinterest inside the gated region.

�� W hen overlap m ixing is used for Pass/Fail m ask testing, togetherwith a well-selected color schem e (for exam ple, default schem e “1”)and the m easurem ent-gate highlighting described above, the tracearea outside the m ask is placed in clear relief.


��

��

White Dark Cyan Ocean Spray Fuchsia

Cyan Cream Ice Blue Raspberry

Yellow Sand Pastel Blue Neon Pink

Green Amber Pale Blue Pale Pink

Magenta Olive Sky Blue Pink

Blue Light Green Royal Blue Vermilion

Red Jade Deep Blue Orange

Light Gray Lime Green Navy Cerise

Gray Apple Green Plum Khaki

Slate Gray Emerald Green Purple Brown

Charcoal Gray Grass Green Amethyst Black


��

��

Analog Persistence provides an analog view of signals whilemaintaining digital data manipulation flexibility.

P ress o r use the D IS P LA Y S E T U P “P ers is tence” m enu

(see page 11–14) to ac tiva te the osc illoscope ’s pers is tencefunctions .

�� W ith trad itiona l ana log ins trum ents , da ta m an ipu la tion and thed irec t com parison o f acqu is itions is p rac tica lly im poss ib le .S ta tis tica l ana lys is is a lso d ifficu lt to perfo rm . N everthe less ,ana log does have certa in advantages. B ecause there is noana log–to–d ig ita l convers ion , the speed o f the ana log scope islim ited on ly by the bandw id th o f its e lec tron ics : s igna ls arem onito red a lm ost continuous ly. T he s tandard D S O (D ig ita lS torage O sc illoscope) m ust capture s igna ls across the tim eperiod a llow ed by the s ize o f its acqu is ition m em ory, thenprocess and d isp lay the ir representa tion . T he tim e needed toprocess the previous acqu is ition lim its D S O speed.

LeC roy’s un ique A na log P ers is tence o ffe rs the advantages o fana log d isp lay in a D S O . T he d isp lay looks like an ana log d isp layand is fas t. B ut it p rov ides the data m anipu la tion , flex ib ility, andsta tis tica l ana lys is on ly found in a d ig ita l ins trum ent.

�� D S O s w ith A na log P ers is tence are fas t because dataaccum ula tion is decoup led from d isp lay. N ew data isaccum ula ted and d isp layed m ore qu ick ly. M oreover, thepers is tence is variab le . The display is generated by repeatedlysam pling am plitudes of events over tim e and accum ulating thesam pled data into three-dim ensional display m aps. These m apscreate an analog-style display. User definable persistence durationcan be used to see how the m aps evolve proportionally over tim e.Statistical integrity is preserved because the duration, or decay, isproportional to the persistence population for each am plitude or tim ecom bination in the data.


��

In add ition , A na log P ers is tence prov ides user-de finab le , pos t-acqu is ition sa tura tion contro l o f the m aps, a llow ing de ta il to beeas ily d raw n out o f the d isp lay.

�� W hen Analog Persistence is selected, each channel and itsassociated persistence data m ap are assigned a single color(whereas the related Color G raded persistence function renders them aps in different colors in the red–to–violet spectrum ). As apersistence data m ap is rendered to the screen, different shades ofits color are assigned to the population ranges between a m inim umand a m axim um population. The m axim um population autom aticallyreceives the brightest shade, the zero or sm allest population thedarkest shade or the background color, and the population rangesbetween zero and the m axim um population the shades in between.

T he in fo rm ation in the low er popu la tions , o r dow n a t the no iseleve l (random trans ien ts ra ther than dom inant s igna ls ) can o ftenbe o f g rea ter in te res t than the res t. T he d is tribu tion o f da ta hereis h igh ligh ted by shades and co lo r so tha t it can be exam ined indeta il.

You can se lec t a sa tura tion leve l o r popu la tion spec ified as apercentage o f the m ax im um popu la tion . A ll popu la tions abovethe sa tura tion popu la tion are then ass igned the brigh tes t shade;tha t is , sa tura ted . A t the sam e tim e, a ll popu la tions be low thesatura tion leve l a re ass igned the rem ain ing shades frombrigh tes t to darkest.

D ata popu la tions and the ir d isp layed shades are dynam ica llyupdated as da ta from new acqu is itions is accum ula ted .


��

��

Press to access the DISPLAY SETUP menus (seepage 11–13) and to select from

� “Standard” or “XY” mode and grids� Persistence� Dot Join� “Single” (1), “Dual” (2), “Quad” (4), or “Octal” (8) grids� Display and grid intensities� “More Display Setup” menus

�� Standard display (m enus on page 11–13) allows presentation ofsource waveform s versus tim e (or versus frequency for FFTs).

XY display (m enus on page 11–16) com pares and contrasts onesource waveform with another, and is used when selected traceshave the sam e tim e or frequency span (tim e/div) and horizontal unit(in seconds or Hertz). XY is autom atically generated as soon as youselect two com patible traces. If you select incom patible traces, awarning m essage is displayed at the top of the screen. And ifcom patible traces are not m atched in tim e, their XY diagram will bedisplayed showing the shift in tim e or frequency between them . (TheΔT or Δf indicator is displayed in the D isplayed Trace Label to the leftof the screen.)

�� In Persistence M ode, the oscilloscope can display points so that theyaccum ulate on-screen over m any acquisitions. Both Analog andColor G raded Persistence can be used in either Standard or XYdisplay. You can m ake eye diagram s and constellation displaysusing Persistence, and the m ost recent sweep can be displayed as a“vector” trace over the Persistence display. Persistence is activatedwhen you select the D ISPLAY SETUP “Persistence” m enu (11–14).


��

�� G rid s tyles , exam ples o f w h ich are show n on the fo llow ing pages,o ffe r a varie ty o f w ays to v iew one or m ore traces in e itherS tandard or X Y d isp lay. A s m any as e igh t traces and grids canbe d isp layed in S tandard m ode us ing the “O cta l” g rid se lec tion(see page 11–12). W hen P aram eters a re used, the spec ia lparam eter-s tyle g rid com es autom atica lly in to p lay. G ridgra ticu les are in te rna lly genera ted , so tha t the in tens ity o f g rids ,as w e ll as o f w aveform s and tex t, can be ad jus ted to the des iredin tens ity. G rids can a lso be b lended w ith d isp layed traces.

Standard Display — Single Grid


��

Standard Display — Dual,Quad Grid


��

Parameter Display — Quad Grid — Full-Screen Mode: trace information normally contained in thetrace labels is arranged beneath the grid in Full Screen.

P ress ing expands the grid d isp lay to fill the entire

screen. P ress ing th is bu tton aga in re turns the grid to its norm als ize . P ress ing R E T U R N in Fu ll S creen m ode rem oves them enus from v iew so tha t w aveform s can be v iew ed in the iren tire ty. T hese reappear w hen you press one o f the M enu-entrybuttons.


��

XY Display grids — XY (left),and XY + Dual (below)


��

�� You can display as m any as e igh t traces a t the sam e tim e w ith the irrespective trace labe ls and any com bination o f m ath , zoom , andm em ories . W hen “O cta l” is se lec ted from the “S tandard” “G rids”m enu (see next page), e igh t separa te grids are m ade ava ilab le .W hen m ore than four traces are d isp layed in S ing le -, D ua l- o rQ uad-grid s tyle , the accom panying trace labe ls becom e sm alle rso tha t as m any as e igh t labe ls can be show n. H ow ever, in O cta lthe labe ls a re a lw ays sm alle r.

Octal style grid, with eight displayed traces and their labels.


��

��

W ith Standard selected, these m enus becom e accessible:

��

This is for activating Persistence (see next m enu). Its functioning iscoupled to the ANALO G PERSIST button.

��

This is used to select Dot Join O N — connecting the sam ple pointswith a line segm ent — or O FF, when only the sam ple points aredisplayed when there are less than 400 points on the screen.

��

This is used for accessing the M O RE DISPLAY m enus (see page11–20).

��

This is for selecting the num ber of grids.

��

This adjusts the screen intensity for the waveform and associatedtext by m eans of the associated m enu knob.

��

This adjusts the screen intensity of the grid by m eans of theassociated m enu knob.

�� If “W’form + Text intensity” is turned down to 0%, thewaveform and text disappear. Press the DISPLAY button to returnautomatically to 90% intensity. If “Grid” is turned down to 0%,press the “Grid intensity” menu button to return this intensity to75%.


��

��

W ith both Standard and “Persistence” On selected in the first m enu,these m enus appear:

��

This is for activating Persistence. W hen On, this can be cleared andreset by pressing the CLEAR SW EEPS button or by changing anyacquisition condition or waveform processing condition. This m enubutton toggles with the ANALO G PERSIST button.

��

Use this to access the “PERSISTENCE” m enus (see next page)

��

This is for accessing the “M O RE DISPLAY” m enus (see page 11–20).

��

This is for selecting the num ber of grids.

��

Use this to select any or all of the displayed traces — On (top m enu)— for saturation adjustm ent.

��

This is for selecting the percentage of saturation. A level of 100%corresponds to the color spectrum being spread across the entiredepth of the persistence data m ap. At lower values, the spectrum willsaturate (brightest color or shade) at the specified percentage value.Lowering the percentage causes the pixels to be saturated at a lowerdata intensity, and allows rarely-hit pixels that are not seen at higherpercentages to becom e visible.


��

�� These m enus appear when Persistence Setup is selected fromDISPLAY SETUP.

��

Select On to show the last acquired trace.

��

This is for selecting the persistence duration, in seconds.

The num ber of sweeps accum ulated (up to one m illion) is displayedbelow the grid.

��

Use this to select whether persistence is applied to all traces or to thetop two traces only.

��

Use this to select the Persistence M ode. W ith Analog selected, eachpersistence data m ap is rendered to the screen in various intensitiesof the trace color. W ith Color Graded, all persistence data m aps arerendered in a red–to–violet spectrum .

��

Use this to select any or all of the displayed traces — if On (topm enu) — for saturation adjustm ent.

��



��

�� W hen XY is selected in the first m enu, these other m enus appear.

��

This is for activating Persistence.

��

This is for accessing XY SETUP (see next page).

��

This is for accessing the M O RE DISPLAY m enus.

��

Use this to select the grid style.

��


��


�� If “W’form + Text intensity” is turned down to 0%, thewaveform and text disappear. Press the DISPLAY button toreturn automatically to 90% intensity. If “Grid” is turned down to0%, press the “Grid intensity” menu button to return thisintensity to 75%.


��

�� W hen the corresponding m enu button for XY SETUP is pressed and

when “Persistence” is OFF, these m enus appear:

��

Use this to select Analog or Color Graded persistence for a singlesweep .

��

This is for selecting the percentage of saturation. At lower values, thespectrum will saturate (brightest color or shade) at the specifiedpercentage value. Lowering the percentage causes the pixels to besaturated at a lower data intensity, and allows rarely-hit pixels thatare not seen at higher percentages to becom e visible.


��

��

W hen XY is selected in the first m enu and Persistence is activated,these m enus appear:

��

Use this to turn Persistence On.

��

This is for accessing XY SETUP using Persistence (see next page).

��

This is for accessing the M O RE DISPLAY m enus.

��

This is for selecting the grid style.

��


��


�� If “W’form + Text intensity” is turned down to 0%, thewaveform and text disappear. Press the DISPLAY button toreturn automatically to 90% intensity. If “Grid” is turned downto 0%, press the “Grid intensity” menu button to return thisintensity to 75%.


��

��

These m enus appear when you press the corresponding m enubutton for “XY–Persist Setup.”

��

This is for selecting the persistence duration, in seconds. Thenum ber of sweeps accum ulated — up to one m illion — is displayedbelow the grid.

��

To select Analog or Color Graded Persistence.

��



��

��

�� Press the button alongside the “More Display Setup” menuto gain direct access to these menus.

��

This is for accessing the Screen Saver controls. W hen enabled, thebuilt-in screen saver w ill blank the screen 10 m inutes after the lastuse of a front panel control. This is a com plete display shutdown ofthe internal screen, resulting in lower power dissipation and systemnoise. The external m onitor, however, does rem ain active during thedisplay shutdown. The front panel LED indicates that the scope is inthe screen-saving STANDBY state. Press any front panel control torestore the screen.

��Use this to select from six preset (1 through 6), or four user (U1through U4) color schem es. W hen a user-custom schem e ischosen, “CHANG E CO LO RS” is added to the list of m enus, enablingthe creation of personal color palettes and the assignm ent of colorsto traces, grids, or any other displayed on-screen object or elem ent(see box on facing page). It also allows preset schem es to be copiedfor easier custom ization.

��This m enu appears when you select one of the four custom colorschem es from the CO LO R SCHEM E m enu (above). It accesses theCHANG E CO LO RS secondary m enu (see page 11–22).

��T his is fo r se lec ting e ither Opaque o r Transparent. W hen thela tte r is chosen, w aveform ob jec ts a re a lw ays v is ib le and the iroverlapp ing reg ions au tom atica lly d is tingu ished by a new andun ique co lo r. W hen dea ling w ith traces o f the sam e type, theforem ost trace is described in the top-le ft trace labe l, the next inthe second-from -top trace labe l, and so on in descend ing ordertow ards the background and the bo ttom o f the screen,respective ly. T h is o rder can be changed by m eans o f theC H A N N E LS T R A C E O N /O FF buttons . For a varie ty o f tracetypes, the order fo llow s tha t described on page 11–3.


��

��

T his is used to tu rn On the M easure G ate func tion , w h ichh igh ligh ts the ga ted param eter reg ion by m ak ing the trace in thereg ion ou ts ide the param eter a neutra l co lo r.

��

This is used to show the data (sam ple) points in Normal or Boldview.

�� The preset (“1–6”) and user-selected (“U1–U4”) custom colorschemes give a particular color to each displayed object. Colorsare assigned to the custom palettes through the CHANGECOLORS “Change” menu (see next page) for:Background: The background color of the entire displayarea.Trace 1.. .4: The color assigned to traces displaying Channel 1,2, 3, or 4.Trace A.. .D: The color assigned to Trace A, B, C, or D.Grid: The default color of the grid.Text: The color assigned to menus, acquisition status andnon-single-source measurements.Cursors: The color assigned to cursors.Warnings: The color assigned to error and warningmessages.Neutral: The color designated as neutral (can be any color inuser palettes), used in ‘Measure-Gate’ region highlighting.Overlays: The color assigned to the menus overlaid on thegrid in Full Screen mode.


��

�� This enables colors to be assigned to displayed objects, and colorschem es to be custom ized.

��

This is for copying one of the six preset color schem es (1 through 6)to a user color schem e (U1 through U4), or one user color schem eto another. Copying m akes custom izing easier by form ing the basisof a personalized palette that can then be developed.

��

This is for executing the copying of the preset schem e to thepersonal color palette.

��

Use this to select a displayed object for color assignm ent (see boxon previous page for details).

��

This is for selecting the color to be assigned to the chosen object.

# # #


��

��

�� Press to access the primary menus for:� Hardcopy settings� Time and date settings for the real-time clock� GPIB and RS-232-C settings� Mass storage utilities (including copy and format and

delete files)� Special modes of operation (including offset behavior,

sequence time-out, cursor units, autocalibration andRemote Control Assistant)

� Signal function at the CAL BNC connector (magnitude,frequency, shape, trigger out, pass/fail use)

�� (see page 12–2)

Use this to access secondary m enu for viewing or changing printersettings.

�� (see page 12–4)

Use this to access the secondary m enu for adjusting the real-tim eclock displayed in the upper left-hand corner of the screen.

�� (see page 12–5)

Use this to access the secondary m enu for viewing or changinginterface settings.

�� (see page 12–10)

Use this to access the M ASS STO RAG E UTILIT IES m enus.

�� (see page 12–19)

Use this to access the SPECIAL M O DES m enus.

�� (see page 12–23)

Use this to access the CAL BNC m enus.


��

�� W hen you select “Hardcopy Setup” from UTILIT IES these m enus

appear:

��Use this to select the output device. This m enu shows the optionsinstalled in the instrum ent. The device can be a port (G PIB, RS232,or Centronics) to which a printer is connected, a storage unit such asa floppy drive or portable hard disk drive (HDD), or the internalprinter. If it is a port, the G PIB & RS232 m enus should be checked toensure that settings are correct. File nam es are assignedautom atically when you copy to a storage unit.

��Select On to start a new page each tim e SCREEN DUMP is pressed.

Press to m ake a copy of the screen display.

��Use this to select the type of printer (see Appendix A), plotter(HP 7470, HP 7550 only), or screen file protocols (T IFF, BM P,HPG L) by m eans of the corresponding m enu buttons or knob.

��T his is fo r choos ing “P ortra it” o r “Landscape” fo rm ats (ava ilab ilityis dependent on “prin ter” cho ice).

��(not shown)T his m enu becom es ava ilab le w hen you choose “T IFF co lo r,”“B M P co lor,” o r “B M P com pr.” It is used to g ive a “B lack ” o r“W hite ” background to the hardcopy reproduction .

��(not shown)Availab le on ly w hen a p lo tte r is se lec ted, th is subm enu o ffe rsthese cho ices o f s ize : A 4 (11” × 8 .5 ”) o r A 5 (8 .5 ” × 5 .5 ”).

��(not shown)Availab le on ly w hen a p lo tte r is se lec ted, th is subm enu is usedfor choos ing the num ber o f pens ins ta lled (the ins trum entassum es tha t the pens are loaded consecutive ly in the low ers lo ts ).


��

�� OOPPTTIIOONNAALL OONN MMOOSSTT MMOODDEELLSS

��

U se th is to se lec t the device to w h ich the ins trum ent is to ou tpu tda ta : in th is case, the op tiona l Int. Printer. T h is m enu show s theoptions ins ta lled in the ins trum ent. T he device can be a port(G P IB , R S 232, o r C entron ics) to w h ich a prin te r is connected , as torage un it such as floppy drive or portab le hard d isk d rive(H D D ), o r the in te rna l p rin te r. If it is a port, the “G P IB & R S 232”m enu shou ld be checked to ensure tha t se ttings are correc t. F ile nam es are ass igned autom atica lly w hen you copy to as torage un it.

��

W hen On, th is genera tes a hard copy o f the screen and sends itto the in te rna l p rin te r a fte r every acqu is ition .

��

T his is fo r se lec ting the expans ion fac tor.

��

T his is fo r choos ing “P ortra it” o r “Landscape” fo rm ats .

��A “persistence” trace cannot be expanded, nor cancursors be shown on an expanded printout.


��

��

�� W hen you select “T im e Date Setup” from UTILIT IES these m enusappear:

��

T his is fo r changing to Daylight Savings T im e.

��

T his is fo r changing back to Standard T im e.

��

Use this to activate the changes m ade with the “Hour M in Sec” and“Day M nth Year” buttons and knobs (see below).

��

Use the corresponding m enu button to toggle between Hour,Minutes, and Seconds; and the associated m enu knob to adjust thevalue.

��

Use the corresponding m enu button to toggle between Day, Mnth,and Year; and the associated m enu knob to adjust thecorresponding value.


��

��

When you select “GPIB/RS232 Setup” from UTILITIES, you canuse the RS-232-C port on the rear panel for remote operation ofthe oscilloscope, and for direct interfacing to a hard-copydevice to output displayed waveforms and other screen data.See the illustration on the next page for RS-232 printer cabling,and “Data to PC” in the Hands-On Guide for computer nine-pincommunication cabling for PC.A printer unit connected to the scope through the RS-232-C port canbe controlled from a host com puter using the scope’s G PIB port. Theoscilloscope's built-in drivers also allow hard copies to be m adewithout an external com puter.

The Rem ote Control Assistant feature allows autom atic detection oferrors during rem ote control operation (see page 12–20).

��

DB9 Pin No. Line Name Description3 T × D Transm itted Data (from the oscilloscope).

2 R × D Received Data (to the oscilloscope).

7 RTS

Request To Send (from the oscilloscope). If the software Xon/Xoff handshake

is selected, it is always TRUE. O therwise (hardware handshake) it is TRUE

when the oscilloscope is able to receive characters and FALSE when the

oscilloscope is unable to receive characters.

8 CTS

Clear To Send (to the oscilloscope). W hen TRUE, the oscilloscope can

transm it; when FALSE, transm ission stops. It is used for the oscilloscope

output hardware handshake.

4 DTR Data Term inal Ready (from the oscilloscope). A lways TRUE.

5 SIG GND Signal Ground

Corresponds to a DTE (Data Terminal Equipment) Configuration


��

�� W hen “G P IB /R S 232 S etup” is se lec ted from U T IL IT IE S thesem enus appear:

��

T his is fo r se lec ting the port fo r rem ote contro l.

��

U se th is to se lec t 7–bit o r 8–bit m ode fo r R S -232com m unica tion . W hen RS-232 is se lec ted , the G P IB in te rface isin “T a lk O n ly” m ode. A ny change becom es e ffec tive im m edia te ly.

��

U se th is to se lec t odd, even, o r none fo r R S -232com m unica tion .

��

T his is fo r se lec ting the num ber o f s top b its fo r R S -232com m unica tion .

��

U se th is to se t the B aud R ate fo r R S -232 com m unica tion us ingthe assoc ia ted m enu knob.

��

U se th is to choose the appropria te G P IB address .

RS-232 cabling can be used in almost every case (for computer cabling see“Transferring Data to PC” in the “Hands-On Guide”).


��

��

When you select “Mass Storage Utilities” from UTILITIES,the “MASS STORAGE” menu group appears (see page 12–10). This menu gives access to the mass storage file systemcontrols. The system supports storage and retrieval of datafiles to and from memory cards, floppy disks, and removablehard disk drive (HDD) media.

�� The M em ory Card structure, based on the PCM CIA II / JEIDA 4.0standard and consists of a DO S partition containing files, as in anyDO S floppy or hard disk. The oscilloscope form ats the card insegm ented contiguous sectors, each of 512 bytes. The scope doesnot support error detection algorithm s such as CRCs or checksuminserted between the sectors. W hen this is done the instrum ent m ayonly be able to read from , but not write to, the card.

�� The floppy supports DO S 1.44 M B and 720 kB form ats.

�� The rem ovable hard disk structure is based on the PCM CIA III /JEIDA 4.0 standard. The m edium is arranged as a DO S partitioncontaining files, as in any DO S floppy or hard disk.

The HDD form at uses 512 bytes per sector and four sectors percluster. O ne cluster is the m inim um file size: any files sm aller than2048 bytes in size will still use one cluster’s allocation of 2048 bytesof disk space. A total of 500k ASCII records can be saved to theHDD portable hard drive.

�� All files are written to, and read from , the current working directory.The default nam e of the working directory is LECRO Y_1.DIR. Thisdirectory is autom atically created when the m edia are form atted. Ifthe m edia are form atted elsewhere — for instance, on a PC — thedirectory w ill be created the first tim e a file is saved to the m em orycard, floppy disk, or rem ovable hard disk.

The working directory can be changed to any valid DO S directorynam e, using the file-nam e preferences m enu. A ll working directoriesare created as sub-directories from the root directory.

The m axim um num ber of files allowed in any one directory is 2400.


��

�� As in M S-DO S, the file nam e can take up to eight charactersfollowed by an extension of three characters. A file is treated as:

� a panel setup if its extension is PNL

� a waveform if its extension is a three-digit num ber

� a waveform tem plate if its extension is TPL

� a hardcopy if its extension is T IF, BM P, or PRT

� an HPG L plot file if its extension is PLT

See also the key to term s, below.

The instrum ent has a predefined nam ing convention for theeight-character file and directory nam es. These default nam es canbe custom ized, as shown in this table. If the new file being stored hasthe sam e nam e as an existing file on the sam e storage m edium , theold file w ill be deleted.

Type Default Name Customized NameM anua lly s to red w ave fo rm files S tt.nnn xxxxxxxx.nnn

Autom atically stored waveform files A tt.nnn xxxxxxxx.nnn

P ane l files P nnn .P N L xxxxxnnn .P N L

H ardcopy files

D nnn .T IFD nnn.B M PD nnn.P R TD nnn.P LT

xxxxxnnn .T IFxxxxxnnn .B M Pxxxxxnnn .P R Txxxxxnnn .P LT

Tem pla te files LE C R O Yvv.TP L C anno t be changed

D irec to ry nam e LE C R O Y_1.D IR xxxxxxxx

S preadshee t S ttnnn .TXT xxxxxnnn .TXT

M atlab S ttnnn .D A T xxxxxnnn .D A T

M athcad S ttnnn .P R N xxxxxnnn .P R N

Key to Termsx a n y l e g a l D O S f i l e - n a m e c h a r a c t e r w the template version number: for example, for a version

2.2, the template is saved as LECROY22.TPL

tt the trace name of C1, C2, C3, C4, TA, TB, TC, TDT IF

B M Ph a r d c o p y g r a p h i c i m a g e f i l e s

nnn a 3 - d ig i t d e c im a l s e q u e n c e n u m b e r s t a r t in ga t 0 0 1 t h a t i s a u t o m a t ic a l l y a s s ig n e d

P R T h a r d c o p y p r i n t e r f i l e s .

P LT H P G L p l o t t e r / v e c t o r f i l e s


��

��

The default notation for waveform files is Stt.nnn for m anually storedfiles and Att.nnn for autom atically stored files, the characters S and Arepresenting the two storage m ethods, respectively.

W hen autom atically generating a file nam e, the system uses theassigned nam e plus a three-digit sequence num ber. If the assignedwaveform nam e is already in the default ‘S tt’ form — such as SC1,STB — the nam e will be m odified to the ‘A tt’ form : AC1, ATB, and soon. A ll other user-assigned nam es rem ain as entered.

�� If Fill is selected and default nam es are used, the first waveformstored will be Axx.001, the second Axx.002, and so on. Thiscontinues until the storage m edium is filled, the file num ber reaches999, or there are m ore than 2400 files in the current workingdirectory.

If Wrap is selected, the oldest auto-stored waveform files w ill bedeleted whenever the m edium becom es full. The rem aining auto-stored waveform files w ill be renam ed: the oldest group of files w illbecom e “Axx.001,” the second oldest “Axx.002,” and so on.

The current sequence num ber is deduced from inspection of all filenam es in the working directory, regardless of file type — panel, hardcopy, or waveform . The highest occupied num eric file-nam eextension of the form ‘nnn’ is determ ined, and the next highestnum ber is used as the current generation num ber for storageoperations.

�� W hen a file generation is deleted, all files designated with the three-digit sequence num ber of the file-nam e extension will be deleted,regardless of file type.

��

The m ass-storage file system indicates m edia size and storageavailability in kbytes where 1 kbyte = 1024 bytes. M any m ediam anufacturers specify the available storage in M bytes where1 M byte = 1 m illion bytes. This results in an apparent m ism atch inspecified versus actual m edia storage availability, when in fact theavailability in bytes is identical.

�� If the write-protection switch of the card or floppy disk being used hasbeen set, the m essage “Device is W rite Protected” w ill be displayedon the upper part of the grid whenever the m edium is accessed forwriting.


��

�� The SRAM m em ory card contains a battery for preserving data.W hen this needs replacing, the m essage “BAD BATTERY” appears.The battery should be changed while the m em ory card is still in theoscilloscope to prevent loss of inform ation. To gain access to thebattery, rem ove the panel on the bottom edge of the card byrem oving the sm all screw.

�� This calls up the prim ary m enus for controlling m ass storage. Therange of “UTILIT IES” available depends on the options installed:

��(OPTION)

Use this to delete files, or to form at or copy a m achine tem plate ontom em ory card. (The U tilities m enus accessed by selection of thisM em ory Card m enu are sim ilar to those accessed for Floppy D isk,shown on the following pages.)

��

Use this to delete files, form at, or copy a m achine tem plate ontofloppy disk. The exam ples on the following pages illustrate thisselection.

��(OPTION)

Use this to delete files, form at, or copy a m achine tem plate onto harddisk. See page 12–14.

��

Use this to set, add, or delete a working directory, or to custom ize filenam es. See page 12–15.

��(IF MORE THAN ONE MASS-STORAGE DEVICE ISAVAILABLE)

This is for copying files from one storage device to another. Seepage 12–18.


��

�� These m enus appear when “F loppy D isk UTILIT IES” is selectedfrom M ASS STO RAG E and

� a floppy has been newly inserted, or

� there is no floppy in the drive

��

Use this to read the floppy disk and display directory contents.


��

�� O nce the floppy disk has been read, these m enus appear. Theydisplay inform ation about the installed storage m edia:

� last “form at” date and tim e

� m em ory size and available free space

� date, tim e, and size inform ation of the selected file on the disk

��

Use this to access a secondary m enu for form atting storage m ediaor for copying the m achine tem plate to it. The tem plate is an ASCIItext file that contains all inform ation required for decoding thedescriptor part of a binary waveform .

��

Use this to delete the file selected in the “F ile” m enu (see below).

��

This is for selecting the file to be deleted, using the associated m enuknob or buttons.


��

�� These m enus appear when “TEM PLATE AND FO RM ATTING ” is

selected from FLO PPY UTIL.

��

Use this to form at the floppy in DO S form at w ith an interleave factorof two, which optim izes throughput to and from the scope.

��

This m enu, which appears only in “FO RM AT FLO PPY,” is used forselecting density: 1.44 MB (HD) or 720 kB (DD).

��

This is for copying the m achine tem plate to the m edium . Them achine tem plate is an ASCII text file that contains all theinform ation required to decode the descriptor part of a binarywaveform .


��

�� These m enus appear when “M ASS STO RAG E,” “Hard D iskUTILIT IES,” and “TEM PLATE AND FO RM ATTING ” are selected.

��

Use this to quickly (15 seconds) clear the portable hard disk drive.

��

Use this for a com plete form atting of the HDD, which isrecom m ended if the disk is non-readable.

��

This is for copying the m achine tem plate to the m edium . Them achine tem plate is an ASCII text file that contains all theinform ation required to decode the descriptor part of a binarywaveform .


��

�� These m enus appear when “M ASS STO RAG E,” “M ass StoragePreferences,” are selected and used for:

� selecting the working directory

� deleting a directory

� accessing the “F ile Nam e Preferences” m enu

� accessing the “Add New D irectory” m enu

��

This is used for selecting the m edium .

��

This is used to access the secondary m enu for defining customnam es for waveform , setup, or hardcopy files (see next page).

��

This is used to delete the directory selected in work with m enu (seebelow).

��

This is for selecting the directory to be used for file storage andretrieval.

��

This is used to access a secondary m enu to add a new directory.


��

�� This m enu group appears when “F ile Nam e Preferences” is selectedfrom the preceding m enu, and is used for defining custom nam es forwaveform , setup, or hardcopy files.

��

Use this to select the character for m odification.

��

This is for restoring the file type selected in the “F ile Type” m enu (seebelow) to its default nam e.

��

This is used to validate the newly defined nam e.

��

This is for m oving back one space and erasing the previouscharacter.

��

Use this to m ove forward to create a space for insertion of acharacter.

��

This is for selecting a character, using the m enu knob.

��

Use this to select the file type to custom ize.


��

�� This is used to define a new directory w ith a custom nam e.

��

This is for creating a new directory.

��

This is for validating the new directory.

��

Use this to m ove back one space and erase the previous character.

��

This is for m oving forward to create a space for the insertion of acharacter.

��

This is for selecting a character, using the m enu knob.


��

�� These m enus, which appear when “M ASS STO RAG E” “F ile

Transfers” is selected, are used to copy files from one m edium toanother.

��(DEPENDING ON OPTIONS INSTALLED)

Use this to select the source (copy from ) and destination (copy to).

��

This is for selecting the type of file for copying.

��

This executes copying.


��

��

When you select “Special Modes” from UTILITIES, thesemenus become available (not all selections may be available).

��accesses:� ��

This is for specifying the tim e-out in Sequence m ode, by m eansof the associated m enu knob to change the value.

�� accesses:��and

� ��This is for specifying the offset behavior of a gain (VO LTS/DIV)

change. The offset can be fixed in Volts or vertical Divisions.

� ��

Use this to set the autom atic recalibration ON or OFF. The

default setting is O N. Turning this off m ay speed up theacquisition, but during that tim e calibration is not assured.

� ��

This is used to control the Global Bandwidth Lim it. W hen On, the

chosen bandwidth lim it applies to all channels; when Off, a

bandwidth lim it can be set individually for each channel. See Chapter5, “Coupling.”

�� Accesses:� ��

This is for selecting from “In” the tim e cursor am plitude units in

Volts or dBm.

��This accesses the “RC ASSISTANT” m enus (see next page)

��This accesses the “USER PREF’S” m enu group (see page 12–21).

��This accesses the “FLASH UPDATE” m enu (see page 12–22).


��

�� U sed fo r m on ito ring rem ote com m ands rece ived th rough theG P IB and R S -232 rem ote contro l ports , the R em ote C ontro lA ss is tan t he lps debug com m unica tions be tw een the osc illoscopeand the P C . W hen ac tiva ted , it d isp lays a log o f the d ia log tak ingp lace th rough the rem ote contro l ports o f the osc illoscope. W hena com m unica tion erro r occurs , R C A ss is tan t g ives the add itiona lm essage “R em ote C ontro l: p rob lem detec ted and logged.”

��

U se th is to se lec t:

Off — T he R C A ss is tan t w ill not cap ture any rem ote com m ands.

Errors Only — T h is se tting d isp lays on ly w rong or incom ple tecom m ands rece ived th rough any rem ote contro l port (th is is thedefau lt se tting a fte r pow er-on).

Full Dialog — T h is se tting captures a ll rem ote com m andsrece ived th rough any rem ote contro l port and d isp lays up to 100lines o f d ia log , a fte r w h ich lines are overw ritten on a firs t-in , firs t-ou t bas is .

RS232 Also — T h is se tting logs the fu ll d ia log and sends it to arecord ing device connected to the R S -232 port. W hen th is isused, com m ands can on ly be rece ived th rough the G P IB port.

S ee a lso the C O M M _H E LP and C O M M _H E LP _LO G com m andsin the R em ote C ontro l M anua l.

��

Turn the knob associated with this m enu to enable scrolling throughthe log. Push the corresponding m enu button to clear the log entirely.


��

�� This lets you custom ize the operation of front panel controls.

��

��

W hen this is On, all front panel buttons when pressed and held in w ill

cursor sequentially through all the choices in their respective m enus.

��

��

W hen On, an aud ib le beep w ill sound w hen you press any fron tpane l bu tton .

��

W hen On, an aud ib le beep w ill sound w hen you tu rn any fron tpane l knob.


��

�� These m enus allow updating of the oscilloscope with new software.Shown here is the full screen warning m essage displayed when“FLASH UPDATE” has been selected from “SPECIAL M O DES.” Thesecond m enu is called “Update Flash” on LC564, LC584, AND LC684SERIES oscilloscopes.


��

��

�� When you select “CAL BNC Setup” from UTILITIES, you canchoose the type of signal output at the CAL BNC connector. Youcan also choose the frequency, amplitude, and pulse shape ofthe calibration signal.In addition, the CAL BNC connector can be used to provide a pulse:

� as an action for PASS/FAIL testing

� at the occurrence of each accepted trigger event (T rigger O ut)

� when the scope is ready to accept a trigger event (T rigger Rdy)

M oreover, a DC level in the range 0.05 V to 1 V in 1 MΩ can beselected.

W hen the instrum ent is switched on, the calibration signal isautom atically set to its default state: 1 kHz, 1 V square wave.

��

U se th is to se lec t the type o f s igna l.

��

U se th is to rese t the C A L B N C output to its de fau lt s ta te .

��

U se th is to se lec t the fo rm o f the ca lib ra tion s igna l.

��

T his is fo r se tting the des ired h igh leve l fo r a ll C A L B N Capplica tions, us ing the assoc ia ted knob. If the B N C output isconnected to an input channe l w ith 50 Ω, the am plitude w ill beha lved.

��

T his is fo r se tting the des ired frequency o f a C A L s igna l in therange 500 H z to 2 M H z, us ing the assoc ia ted knob.

# # #


��

BLANK PAG E


��

��

�� Press WAVEFORM to store waveforms to internalmemory (M1, M2, M3, or M4) in LeCroy’s binary format. Youcan also store waveforms in binary or ASCII format onfloppy disk, memory card, or removable hard disk (HDD)where available.W hen Binary and Flpy (o r one o f the op tiona l m ed ia is se lec ted),the m enus show n on th is page appear. W hen an in te rna lm em ory (M 1 to M 4) is se lec ted , how ever, ne ither the “D ataForm at” nor “A uto-S tore” m enus appear. In e ither case, thew aveform w ill be s to red au tom atica lly in the se lec ted m em ory inb inary fo rm at w hen you press the “D O S T O R E ” m enu button .

W hen ASCII is se lec ted (as show n on the next page) the scopew ill s to re the w aveform in an A S C II fo rm at. B ut th is w ill c rea te anoutput file requ iring 10 to 20 tim es the d isk space o f the orig ina lLeC roy b inary file . Furtherm ore , w aveform s s to red in A S C IIfo rm at cannot be reca lled to the scope.

��

� The capacities of the Reference and Zoom & Math memorieseach match those of the acquisition memories. For every unitof record length per channel, a point can be stored in any oneof the four M reference memories, and the same number ofpoints for each “Zoom & Math” trace.

� When more acquisition memory is achieved by combiningchannels, a single long trace can consume all the instrument’sReference memory or “Zoom & Math” trace capacity. If thishappens, a warning message will be displayed to prevent theaccidental storage of a new trace to a reference memoryalready in use.


��

��

This is for choosing the data form at, as described on the previouspage. W hen ASCII is selected, the prim ary “Setup ASCII Form at”m enu appears im m ediately beneath this m enu, giving access to thesecondary “ASCII SETUP” m enu (see next page). W hen Binary isselected, the waveform is stored in binary form at.

��

This appears only when ASCII is highlighted in “Data Form at,” as shownhere. It is used for accessing the secondary “ASCII SETUP” m enu (seenext page).

��

This is for autom atically storing waveform s after each acquisition. Fillstores until the m edium is filled, while Wrap stores continuously,discarding the oldest files on a first-in, first-out basis.

��

This stores in accordance with specifications m ade in the “store” and “to”m enus (see below).

��

This is for selecting the waveform . All displayed can only be selectedwhen you are storing on optional storage m edia.

��

Use this to select the internal m em ories M1, M2, M3, or M4, when“Binary” is selected in the “Data Form at” m enu, as shown on the previouspage. Alternatively, select the optional Card, Flpy, or HDD, when ASCIIis selected from the “Data Form at” m enu, as shown here.


��

��

��

This secondary m enu, accessed through SETUP ASCII FO RM AT,offers a choice of ASCII form ats. (For details on each form at, seeAppendix E).


��

��

�� Press WAVEFORM to recall a waveform frominternal memory, floppy, or the optional memory card orremovable hard disk (HDD).

��

Use this to select the storage m edium from which to recall, internalMemories in this case.

��

Use this to execute recall based on the selections m ade in the “fromM em ory” and “to” m enus (see below). At the sam e tim e it resets thehorizontal and vertical positions as well as the zoom s, showing thefull contents of the m em ory at its original m agnification.

��

This is for selecting the source m em ory.

��

Use this to select the destination trace.

��Performing a recall operation from an internal memoryto Trace A–D overrides any previous definition of thedestination trace.


��

�� FFLLOOPPPPYY DDIISSKK OORR OOPPTTIIOONNAALL SSTTOORRAAGGEE DDEEVVIICCEE

��

This selects the device or m edium on which the file is stored: HDD,Card, or Flpy.

��

Use this to execute recall based on the selections m ade in the “F ile”and “to” m enus (see below).

��

This selects the file in which the waveform is stored, using theassociated m enu knob.

��This is for selecting the destination m em ory. If All � is selected, up

to four files w ith the sam e three-digit num eric extension as thecurrent “F ile” selection will be recalled into m em ories M 1 to M 4.

# # #

* T he files lis ted w ill be those in the current w ork ing d irec tory.


��

BLANK PAG E


��

��

The cursors are basic and important tools for measuringsignal values.

In S tandard D isp lay M ode, Amplitude (vo ltage) cursors ,represented by dashed lines spann ing the w id th o f the screen,m ove up and dow n the grid p ixe l by p ixe l.

Time cursors , represented by arrow s or c ross-ha ir m arkers tha tm ove a long the w aveform (see sym bols a t le ft), can be p laced a ta des ired tim e to read the am plitude o f a s igna l a t tha t tim e, andm oved to every po in t acqu ired.

W hen a T im e cursor is p laced on a da ta po in t, a c ross-barappears a t the ta il o f the arrow , and a t top and bo ttom o f thecross-ha ir m arker.

In Absolute m ode a s ing le cursor is used. R ead ings fo ram plitude (us ing A m plitude cursors) o r tim e and am plitude (us ingT im e cursors) can be d isp layed a t the cursor loca tion . M easuredvo ltage am plitudes are re la tive to g round; m easured tim es arere la tive to the trigger po in t.

In Relative m ode, a pa ir o f A m plitude or T im e cursors is used,provid ing read ings on the d iffe rence betw een the tw o inam plitude, o r tim e and am plitude, respective ly.

A m plitudes are show n in the T race Labe l fo r each trace. W henT im e cursors are used, the tim e is show n be low the grid . A nd inR ela tive M ode the frequency correspond ing to the tim e in terva lbe tw een the cursors is a lso d isp layed there .

W hen there are few data po in ts d isp layed, T im e cursor pos itionsare linearly in te rpo la ted betw een the data po in ts . T im e cursorsm ove up and dow n a long these s tra igh t-line segm ents .

�� W hen using Persistence, Am plitude cursors are the sam e as inStandard D isplay (see above). T im e cursors are vertical barsspanning the height of the screen and m oving across it.


��

�� In XY D isplay, Absolute Am plitude cursors appear as horizontal andvertical bars that can be m oved up and down and side-to-side acrossthe screen. Relative Am plitude cursors are pairs of bars that m ove inthe sam e way. Absolute and Relative T im e cursors behave as theydo in Standard D isplay.

Com binations of the am plitude values are shown on the left-handside of the grid in the following top-to-bottom order:

1. ΔY value / ΔX value .................... Ratio

2. 20 ∗ log 10 (ratio) ....................... Ratio in dB units

3. ΔY value ∗ ΔX value ................... Product

4. � = arc tan (ΔY / ΔX)

range [–180° to +180°] ...................... Angle (polar)

5. r = sqrt (ΔX ∗ ΔX + ΔY ∗ ΔY)...... Radius (distance to origin)

The definition of ΔX and ΔY depends on the cursor used. The tablebelow shows how ΔX and ΔY are defined for each type ofm easurem ent.

��

TAbs

AAbs ARel O rg = (0,0) Org = VXOffset

VYOffset

TRel

�X VXRef – 0 VXDif – VXRef VXRef – 0 VXRef – VXOffset VXDif – VXRef

�Y VYRef – 0 VYDif – VYRef VYRef – 0 VYRef – VYOffset VYDif – VYRef

W HERE:

AAbs Absolute Am plitude cursors VXRef V o ltage o f the R e fe rence cu rsor on the X trace

ARel Relative Am plitude cursors VYRef V o ltage o f the R e fe rence cu rsor on the Y trace

TAbs Absolute Tim e cursors VXDif V o ltage o f the D iffe rence cu rsor on the X trace

TRel Relative Tim e cursors VYDif V o ltage o f the D iffe rence cu rsor on the Y trace

Org Origin


��

�� Press to access menus that let you customize specialfunctions. The contents of the Custom Menu will varyaccording to the options installed in the oscilloscope.

LLCC668844 SSEERRIIEESS OONNLLYY

Press the CURSO R/M EASURES button; the following options will bedisplayed:

��R efer to “M easure – C ursors” on page 14-5 o f th is m anua l.

��R efer to “P aram eters : A utom atic M easurem ents” s ta rting onpage 14-8 , and A ppend ix D o f th is m anua l.

��R efer to “P ass/Fa il T es ting” on page 14-13 o f th is m anua l.

��R efer to C ustom M enu on page 14-4 o f th is m anua l.


��

�� (continued)

LLCC668844 SSEERRIIEESS OONNLLYY

Press the CUSTOM button to access these custom applications:

��T his w izard s teps you th rough jitte r tim ing and m easurem entse tups. R efer to the J itte r and T im ing A na lys is (JTA ) M anua l.

��R efer to the M ask T ester O pera tor’s M anua l.

��R efer to the P M A 1 S oftw are O pera tor’s M anua l.

��R efer to the D D FA : D isk D rive Fa ilu re A na lys is O pera tor’sM anua l.


��

�� Press — to access the “M EASURE” Setup m enus.

��

Use this to select Cursors.

��

This is for selecting Time (tim e or frequency cursors) or Amplitude(voltage or am plitude cursors).

��

Use this to toggle between Relative and Absolute. The first displaystwo cursors (Reference and D ifference) and indicates either thevoltage, or tim e and voltage, between the two. The second shows asingle cursor that indicates either voltage com pared to ground level,or this and tim e com pared to the trigger point.

��

Use this to select Diff – Ref, which shows the num erical differencebetween D ifference and Reference cursor am plitudes. A lternatively,Diff & Ref displays the am plitude values for each cursor. This is notavailable in persistence m ode.

��

Use this to control the Reference cursor that is available w ithRelative cursors, using the associated m enu knob. W ith “T rack” ON,both Reference and D ifference cursors are controlled by theassociated knob, and m ove together. A constant tim e or voltageinterval is m aintained between them . This tracking interval isrepresented by a bar — horizontal for tim e; vertical for voltage —appearing at the top and left-hand edge of the grid, respectively.

��

This is for controlling the D ifference cursor, available when Relativeis selected from “type” (see above), using the associated m enuknob.

��(not shown)This is for controlling the Absolute cursor, available when Absoluteis selected from “type” (see above), using the associated m enuknob.


��

��

The instrument can determine certain signal propertiesautomatically, using signal parameters. Standard parametersare listed and described in Appendix D of this manual.*

For com m on m easurem ents on a lone signal, param eters can bem easured in either of two standard classes or m odes, in theam plitude or tim e dom ain.

O n different signals, they can be custom ized and used to determ ineup to five of the quantities on the param eter list. Custom izedparam eter m easurem ents can also be used for Pass/Fail testingagainst chosen lim its (see page 14–15). Several other m odes areavailable, according to the param eters and options installed in theoscilloscope (not all m odes illustrated m ay be available).

Statistics on the param eter values are accum ulated and can bedisplayed for all m odes.

In addition to the overall num ber of sweeps used, each param eterhas its average, lowest, and highest value. The standard deviation ofthe param eter is also calculated.

�� The algorithm s that determ ine pulse waveform param eters are ableto detect those situations where the m athem atical form ulas m ay beapplied. However, the results obtained should be interpreted withcaution. In such cases the scope displays the nam e of the param eterand its value, which are separated by a graphic sym bol. The sym bolprovides inform ation about the param eter, or issues a warning. Thefollowing table explains these sym bols.

* A w ide range of additional param eters is available in the specialized

software packages, such as W P03, described in the O perator’sManuals for those packages.


��

��

The parameter has been determined for severalperiods (up to 100), and the average of thosevalues has been taken.The parameter has been determined over anintegral number of periods.

The parameter has been calculated on a histogram.

Insufficient data to determine the parameter.

��

Amplitude histogram is flat within statisticalfluctuations; minimum and maximum are used toassign top and base.Only an upper limit could be estimated (the actualvalue of the parameter may be smaller than thedisplayed value.

The signal is partially in overflow.

The signal is partially in underflow.

The signal is partially in overflow and in underflow.


��

��

For a single trace, this m ode m easures:

� peak-to-peak (am plitude between m axim um and m inim um sam plevalues)

� m ean of all sam ple values

� standard deviation

� root m ean square of all sam ple values

� am plitude of the signal

��Use this to select Parameters.

��This is for selecting the Standard Voltage m ode.

��T his is fo r tu rn ing On d isp lay o f the param eter’s average, low est,h ighest, and s tandard devia tion , as w e ll as the num ber o f sw eepsinc luded in the s ta tis tics . T he num ber o f sw eeps is c leared eachtim e you change the acqu is ition cond itions , o r w hen you pressthe C LE A R S W E E P S button . A s long as Parameters ish igh ligh ted in the top m enu, the accum ula tion o f s ta tis ticscontinues, even if the s ta tis tics a re no t show n.

��U se th is to se lec t the trace fo r w h ich the vo ltage param eters a rem easured. T he cho ices ava ilab le in th is m enu w ill depend on thetraces d isp layed (a m ax im um of four traces can be d isp layed).H ere traces 1 and 2 are d isp layed and 2 is se lec ted.

��U se th is to de term ine the s ta rting po in t (in screen d iv is ions) fo rparam eter m easurem ents , us ing the assoc ia ted m enu knob.“T rack ” On links contro l o f the s ta rting and end po in ts o f theparam eter m easurem ent so tha t they can be m oved together,us ing the assoc ia ted m enu knob.

��Use this to determ ine the end point in screen divisions. It also indicatesthe total num ber of data points used for the m easurem ents.


��

��

For a single trace, this m ode m easures:

� period

� w idth (at 50% am plitude)

� rise tim e (10–90% of am plitude)

� fall tim e (90–10% of am plitude)

� delay (from trigger to first 50% am plitude point)

��Use this to select Parameters.

��This is for selecting the Standard Time m ode.

��This is for turning On display of the param eter’s average, lowest,highest, and standard deviation, as well as the num ber of sweepsincluded in the statistics. The num ber of sweeps is cleared each tim eyou change the acquisition, or when you press the CLEAR SW EEPSbutton.

As long as Parameters is highlighted in the top m enu, theaccum ulation of statistics continues, even if the statistics are notshown.

��This is for selecting the trace for which the tim e param eters are to bem easured. T he cho ices ava ilab le in th is m enu w ill depend on thetraces d isp layed (a m ax im um of four traces can be d isp layed).H ere traces 1 and 2 are d isp layed and 2 se lec ted .

��Use this to determ ine the starting point (in screen divisions) forparam eter m easurem ents. “T rack” On links control of both thestarting and end points of the param eter m easurem ent so that theycan be m oved together, using the associated m enu knob.

��Use this to determ ine the end point in screen divisions. It alsoindicates the total num ber of data points used for the m easurem ents.


��

��

In this m ode, up to five param eters can be displayed for varioustraces.

��

This is for selecting Parameters.

��

This is for selecting the Custom m ode.

��

This is for turning On display of the param eter’s average, lowest,highest, and standard deviation, as well as the num ber of sweepsincluded in the statistics. The num ber of sweeps is cleared each tim eyou change the acquisition conditions, or when you press the CLEARSW EEPS button.

As long as Parameters is highlighted in the top m enu, theaccum ulation of statistics continues, even if the statistics are notshown.

��

This is for accessing the secondary “CHANG E PARAM ” m enu (seefollowing pages).

��

Use this to determ ine the starting point (in screen divisions) forparam eter m easurem ents. “T rack” On links control of the startingand end points of the param eter m easurem ent so that they can bem oved together, using the associated m enu knob.

��

Use this to determ ine the end point in screen divisions.


��

�� This is for m odifying param eters.

��

Use this to select up to five different param eters for m odification.

��

Use this to specify the category of param eter. W hen All is selected,the “m easure” m enu (see below) w ill feature all param eters.However, when a particular category is selected, only thoseparam eters in the category are shown.

��

This is for deleting all param eters previously selected.

��

Use this to choose the new param eter to be m easured on this line.W hen you select “– –” the line is not used.

��

This is for selecting the channel or trace on which the param eter w illbe m easured.


��

�� Param eters can be custom ized to m eet specific needs.

��

Use this to select up to five different param eters for m odification.

��

Use this to specify the category or type of param eter.

��Δ��

This calls up the Δt@lv custom ization m enu (see next page).

��

Set at Δt@lv.

��

Select the channel — 1, 2 (3 or 4) — or m em ory (A, B, C, or D) bym eans of the associated m enu button. Use the associated knob todecide from which, and to which, channel the m easurem ent is to bem ade.


��

�� This is for customizing the measure parameter (Δt@lv in thiscase). See Appendix D for descriptions of all standardparameters.

��

This is for selecting whether the levels should be absolute, or apercentage of the peak-to-peak signal value.

��

Use this to set the hysteresis division. A voltage band is extendedequidistantly above and below the selected level. In order for thesignal to be considered valid, and not as noise, the signal m ustexceed or cross the upper or lower lim its of this band by half thehysteresis division setting.

��

This is for selecting the voltage or am plitude percentage setting ofthe level on the waveform at which the tim ing is to be m easured. It isalso used to select whether the m easurem ent should be m ade on aPositive (rising) edge, or a Negative (falling) edge; or, if First isselected, on either type of edge.

��

This is for selecting the voltage or am plitude percentage setting ofthe level on the waveform at which the tim ing is to end. It is also usedto select whether it should finish on a Positive (rising) edge or aNegative (falling) edge; or, if First is selected, on either type of edge.


��

�� This is for customizing the measure parameter (Δc2d+ in thiscase). See Appendix D for descriptions of all standardparameters.

��

Use this to set the hysteresis division. A voltage band is extendedequidistantly above and below the selected level. In order for thesignal to be considered valid, and not as noise, the signal m ustexceed or cross the upper or lower lim its of this band by half thehysteresis division setting.

��

Use this to select the clock edge or edges used for this param eterm easurem ent.

��

This is for selecting the data edge or edges used for them easurem ent.


��

��

Parameters can also be used in performing Pass/Fail tests.These tests require a combination of measurements withinchosen limits, and invoke an action when the test eitherpasses or fails, depending on which has been specified.Signals can also be Pass/Fail tested against a tolerancemask.U p to five param eters can be tes ted aga ins t lim its a t the sam etim e. In to le rance m ask tes ting , a trace can be com pared to ato le rance m ask .

W hether the tes ts pass or fa il, any or a ll o f the fo llow ing ac tionscan be invoked:

� S top capturing fu rther s igna ls .

� D um p the screen im age to a hardcopy un it.

� S tore se lec ted traces to in te rna l m em ory, to a m em ory card(optiona l), o r to a floppy d isk .

� S ound the buzzer.

� E m it a pu lse on the C A L B N C .

T he P ass/Fa il d isp lay w ill show :

� resu lts on the curren t w aveform s

� the num ber o f events pass ing

� the to ta l num ber o f sw eeps trea ted

� ac tions to be taken


��

��

��

Use this to select Parameters.

��

Use this to select Pass or Fail.

��

This is for turning testing Off or On. Turn testing off only to observethe param eter variations.

��

Use this to access the secondary “CHANG E TEST” m enu (see nextpage).

��

Use this to determ ine the starting point, in screen divisions, forparam eter m easurem ents.

��

Use this to determ ine the end point in screen divisions.


��

��

��

Use this to select up to five different param eters for m odification.(See “Action” selection on page 14–22).

��

Use this to select Param or, if no test is required, --- (No Test).

��

To select “Param”.

��

Use this to delete all tests previously selected.

��

This is for selecting the new param eter to be m easured on this line.W hen “– –” is selected the line is not used.

��

This is for selecting the channel or trace on which the param eter w illbe m easured.


��

��

��


��

Use this to Select Param or --- (No Test) if no test is required on theselected line (“M ask” selection, page 14–19).

��

Use this to select Limit (“Param ” 14–17).

��

This is for deleting all tests previously selected.

��

This is for selecting the appropriate relation: less than or greaterthan.

��

Use this to choose one of three m odifications to a lim it: its m antissa,exponent, or the num ber of digits in its m antissa. The correspondingm enu button is used to select, and the associated knob to m odify,the num ber in that field.

��

Use this to set a lim it to the latest m easured value — a starting valuefor the final adjustm ent.


��

��

��


��

This is for selecting Mask or --- (No Test) if no test is required on theselected line (see “Param ” on page 14–17).

��

Use this to access the secondary m enu for m odifying m ask settings.

��

This is for choosing the m ask test condition.

��

Use this to select channel or trace for testing.

��

This is for choosing the m ask test condition.

��

Use this to select a m ask trace.

��Pass/Fail testing on a mask is affected by horizontaland vertical zooming of the mask trace. The test will bemade inside the area bordered by the parameter cursors.Timebases of the mask and the trace under test should beidentical. For visual mask testing, a single grid should beused when you are performing a mask test on a singletrace. A two-grid display should be used for testing on twotraces.


��

��

��

Use this to select W’form.

��

This is for selecting D=M4 if the m ask is to be autom aticallydisplayed on the screen. O therwise select M1, M2, M3, or M4.

Using “RECALL W ’FO RM ” (see previous chapter), m em ories M 1–M 4 can be recalled to traces A to D for display.

��

Use this to generate an inverted m ask.

��

This is for selecting the waveform to be used as reference. Them ask will be generated around this waveform .

��

Use this to generate the m ask.

��

This is for selecting tolerance in am plitude, by m eans of theassociated knob.

��

This is for selecting tolerance in tim e, by m eans of the associatedknob.


��

�� FFLLOOPPPPYY DDIISSKK OORR OOPPTTIIOONNAALL SSTTOORRAAGGEE DDEEVVIICCEE

��

Use this to select the device.

��

This is for selecting D=M4 to autom atically display the m ask on-screen, or M1, M2, M3, or M4.

��

This is for generating an inverted m ask.

��

Use this to recall the m ask.

��

Use this to select the appropriate m ask, by m eans of the associatedknob.


��

��

Depending on the test result certain actions can be taken:

��

This is for selecting Action.

��

Use this to delete all previously selected actions.

��

Use this to determ ine if the action will be taken on PASS or FAILresult.

��

This is for selecting the action (Dump in this exam ple). The selectedaction will then be activated from the following subm enu.

��

Use this to perform (Yes) or disable (No) the action chosen in the“Then” m enu (see above). The choice will be echoed alongside thealready selected action in the “Then” m enu.

# # #


��

��

�� Press to access the menus used for saving orrecalling configurations — panel setups — to or from non-volatile memory, floppy disk, memory card, or portable harddisk (HDD), depending on options installed.

��

U se th is to save a pane l se tup or reca ll one a lready saved. W henyou se lec t Save (as show n here) the “T O S E T U P ” m enusappear. W hen you se lec t Recall, the “FR O M S E T U P ” m enusappear

��...� ...��or�...�

T his is fo r saving any o f four poss ib le se tups.

��

T his is fo r sav ing a se tup to floppy, m em ory card , o r hard d isk(H D D ), depend ing on op tions .


��

��

U se th is to save or reca ll a pane l se tup . W hen you se lec t Save(as show n on the prev ious page) the “T O S E T U P ” m enusappear. W hen you se lec t Recall (as show n here) the “FR O MS E T U P ” m enus appear.

��...� ...��or�...�

T his is fo r reca lling any o f four poss ib le saved se tups. In theexam ple show n here , a ll four poss ib le se tups have been s tored.W hen no se tup has been s tored, tha t m enu w ill ind ica te “E m pty.”

��

U se th is to choose a de fau lt se tup s to red in the scope.

��

T his is fo r access ing the secondary “R E C A LL S E T U P S ” m enu toreca ll a se tup s tored on floppy, m em ory card , o r portab le hardd isk (H D D ), depend ing on the options ins ta lled .


��

��

��

T his is fo r se lec ting the device from w h ich to reca ll a se tup:floppy, m em ory card , o r portab le hard d isk (H D D ), depend ing onthe op tions ins ta lled .

��

U se th is to perfo rm the reca ll o f the se tup se lec ted in the “F ile ”m enu (see be low ).

��

T his is fo r se lec ting the s to red se tup , us ing the assoc ia ted m enuknob.

# # #


��

B LA N K P A G E


��

��

Press to open the “STATUS” menu and access full-screen summaries of the oscilloscope’s system status orother functional status.

�� T his screen show s vertica l sens itiv ity, p robe a ttenuation , o ffse t,and coup ling fo r each channe l, as w e ll as tim ebase and triggers ta tus sum m aries .


��

�� T his screen show s the seria l num ber o f the scope, firm w arevers ion , and the so ftw are and hardw are op tions ins ta lled .

T he “S oftw are O ptions” m enu accesses the “A D D O P T IO N K E Y”m enu, w h ich le ts you ac tiva te new so ftw are by inputting a code.You sim ply provide LeCroy with the serial num ber, soft versionnum ber, and scope ID (all displayed on this screen), as well as orderinform ation. LeCroy provides a unique option key that you can enterfrom the instrum ent’s front panel.

T he “M O R E V E R S IO N IN FO R M A T IO N ” m enu is used to perfo rma cyc lic redundancy check (C R C ) o f the in te rna l firm w are , andgenera tes a checksum tha t can be used to ensure tha t thefirm w are is uncorrup ted .


��

�� T his show s user tex t in the w aveform descrip to r* and triggertim ing in fo rm ation . W hen “T ext & T im es” is se lec ted the “fo r” and“S e lec t” m enus show n here a lso appear, a llow ing a trace orm em ory to be se lec ted and a segm ent range to be spec ified fo rin fo rm ation .

* R e fer to the R em ote C ontro l M anua l.


��

�� This screen provides detailed status inform ation on channels,m em ories, zoom and m ath, or displayed traces. These are specifiedusing the bottom m enu, which appears when “W aveform ” is selectedfrom the top m enu.


��

�� This screen shows how m uch m em ory is being used and how m uchrem ains free. M em ory allocation: m em ories M 1–M 4 can be selectedand then cleared using the “CLEAR INACTIVE” m enu. T heded ica ted pers is tence da ta m aps fo r each channe l a redynam ica lly c rea ted , res ized, and de le ted as necessary. T hea lloca tion o f m em ory to each o f these da ta m aps w ill appear inth is m enu. P ers is tence da ta m aps are c leared us ing the C LE A RS W E E P S button .

# # #


��

BLANK PAG E


��

��

�� Bandwidth (�3 dB)� LC334, LC374 Series: @ 50 Ω: DC to 500 M Hz @ 1 MΩ D C :

D C to 500 M H z typ ica l a t p robe tip

� LC534, LC574 Series: @ 50 Ω: DC to 1 G Hz

@ 1 MΩ D C : D C to 500 M H z typ ica l a t p robe tip

� LC564, LC584 Series: @ 50 Ω: DC to 1 G Hz (2 m V/div: DC to

200 M Hz, 5 m V/div: DC to 600 M Hz); @ 1 MΩ D C : D C to 500

M H z typ ica l a t p robe tip

� LC684 Series: @ 50 Ω: DC to 1.5 G Hz (2 m V/div: DC to 200

M Hz, 5 m V/div: DC to 600 M Hz); @ 1 MΩ D C : D C to 500 M H z

typ ica l a t p robe tipW ith PP005 passive probe as standard for all models; active probes optional.Number of Channels: 4Number of Digitizers: 4Max. Sample Rate Window (Also see tables on the following pages.)

� LC334, LC534 Series: 4 m s @ 2 G S/s in single-shot m ode

� LC374 Series: 0.25 m s @ 2 G S /s in s ing le -shot m ode

� LC574 Series: 2 m s @ 4 G S /s in s ing le -shot m ode

� LC564 Series: 62.5 µs @ 4 G S /s

� LC584 Series: 2 m s @ 8 G S /s

� LC684 Series: 2 m s @ 8 G S /s

Sensitivity� LC334 Series: 2 m V /d iv to 5 V /d iv , 50 Ω, fu lly variab le

2 m V /d iv to 5 V /d iv , 1 MΩ, fu lly variab le

� LC374, LC534, LC574, LC564, LC584 Series: 2 m V /d iv to 1

V /d iv , 50 Ω, fu lly variab le


� LC684 Series: 2 m V /d iv to 1 V /d iv , 50 Ω, fu lly variab le


�� Where aparticular series is NOTmentioned, thespecification applies toall LeCroy color DSOs.Where the series ismentioned withoutreference to aparticular model, thespecification applies toall models in the series.Specifications are liableto change withoutnotice. For the most up-to-date information,consult the latestproduct data sheets,available from LeCroyoffices.


��

Offset Range� LC334 Series: 2 .00 to 9 .99 m V /d iv : ±120 m V

10.0 to 199 m V /d iv : ±1 .2 V0.2 to 5 .0 V /d iv : ±24 V

� LC374, LC534, LC574, LC564, LC584 Series:2.00 to 4 .99 m V /d iv : ±400 m V5.00 to 99 m V /d iv : ±1 V0.1 to 0 .99 V /d iv : ±10 V

1.0 to 10 V /d iv : ±100 V (1 MΩ on ly)

� LC684 Series: 2 .00 to 4 .99 m V /d iv : ±400 m V

5.0 to 99 m V /d iv : ±1 .0 V0.1 to 1 .0 V /d iv : ±10 V5.0 to 100 m V /d iv : ±1 .0 V

102 m V to 2 .0 V /d iv (1 MΩ on ly): ±20 V

LX X X -O M -E R ev K IS S U E D : D ecem ber 1999 ��

��

��

MEMORY PER CHANNEL (IN POINTS)

MODELCHANNELS USED

(PEAK DETECT ON/OFF)ON SERIES…

MAX. SAMPLERATE

A AM AL

ACTIVECHANNELS

Any Channel (Peak Detect OFF)

LC334, LC534 Series 500 MS/s 100 k 500 k 2 M

LC374 Series 1 GS/s 100 k – –

LC574 Series 1 GS/s 100 k 500 k 2 M

All

Any Channel (Peak Detect ON)

LC334, LC534 Series

LC374 Series

LC574 Series

100 MS/s data+

400 MS/s peaks

50 k data+

50 kpeaks

250 k data+

250 k peaks

1 M data+

1 M peaksAll

Paired Channels (Peak Detect OFF)

LC334, LC534 Series 1 GS/s 250 k 1 M 4 M

LC374 Series 2 GS/s 250 k – –

LC574 Series 2 GS/s 250 k 1 M 4 M

CH 2&

CH 3

All Channels Combined (Peak Detect OFF)

LC334, LC534 Series(by PP093 Adapter) 2 GS/s 500 k 2 M 8 M

LC374 Series (withoutexternal adapter) 2 GS/s on CH 2 500 k – –

LC574 Series (by PP093Adapter) 4 GS/s 500 k 2 M 8 M

One


��

��

MEMORY PER CHANNEL (IN POINTS)

MODELCHANNELS USED

ON SERIES…

MAX.SAMPLE

RATEA AM AL AXL

ACTIVE CHANNELS

Any Channel

LC564 Series 2 GS/s 100 k – – –

LC584 Series 2 GS/s 100 k 500 k 2 M 4 MAll

Paired Channels

LC564 Series 4 GS/s 250 k – – –

LC584 Series 4 GS/s 250 k 1 M 4 M 8 MCH 2 & CH 3

All Channels Combined

LC584 Series 8 GS/s 500 k 2 M 8 M 16 M

One (CH 2, or anydisplayed channelin Auto-Combine

Mode)


��

��

MEMORY PER CHANNEL (IN POINTS)MODEL

CHANNELS USED MAX.SAMPLE

RATE D DM DL DXL

ACTIVECHANNELS

Any Channel

LC684 Series 2 GS/s 100 k 500 k 2 M 4 M All

Paired Channels

LC684 Series 4 GS/s 250 k 1 M 4 M 8 M CH2 & CH3

All Channels Combined

LC684 Series(by PP096Adapter)

8 GS/s 500 k 2 M 8 M 16 M One


��

Scale Factors: There is a w ide range of probe attenuation factorsavailable.

DC Accuracy: ±1% typ ica l; guaranteed ≤ ±2% fu ll sca le

(e igh t d iv is ions) a t 0 V o ffse t

� LC564, LC584 Series: ±(1% fu ll sca le + 1% offse t va lue) a t

ga in ≥10 m V /d iv

� LC684 Series: ±(2% fu ll sca le + 1% o ffse t va lue) a t ga in ≥10

m V /d iv

Vertical Resolution: 8 b its

Bandwidth Limiter� LC334 Series: 30 M H z

� LC374, LC534, LC574 Series: 25 M H z, 200 M H z

� LC564, LC584, LC684 Series: 25 M H z and 200 M H z typ ica l

Input Coupling: A C , D C , G N D

Input Impedance:� LC334 Series: 10 MΩ//15 pF (system capacitance using PP005)

� LC374, LC534, LC574, LC564, LC584 Series: 10 MΩ//11 pF

(system capacitance using PP005), or 50 Ω ±1%

� LC684 Series: 10 MΩ//11 pF (system capacitance using PP005),

or 50 Ω ±1.25%

Max. Input: 50 Ω: ±5 V DC (500 m W ) or 5 V rm s

� LC334: 1 MΩ — 250 V m ax (D C + peak A C ≤10 kH z)

� LC374, LC534, LC574, LC564, LC584 Series: 1 MΩ: 400 V

m ax. (D C + peak A C ≤10kH z)

� LC684 Series: 1 MΩ: 100 V (D C + peak A C @ 10 kH z)

SMARTMemory: T he to ta l m em ory m anagem ent sys tem

dynam ica lly m anages acqu is ition m em ory to guarantee tha ts igna ls a re a lw ays sam pled a t the h ighest poss ib le sam ple ra teand tha t sys tem R A M and m icroprocessor resources are a lw aysoptim a lly em ployed.


��

System Random Access Memory:

��

LC334A LC374A LC534A LC574ALC334AM LC534AM LC564A LC574AM

8

LC334AL LC534AL LC564A LC584A LC584AM 16LC684D LC684DM 16

LC574AL LC584AL LC584AXL 64LC684DL LC684DXL 64

�� Random Interleaved Sampling (RIS): for repetitive signals from :

� LC334, LC534 Series: 1 ns /d iv to 5 µ s /d iv

� LC374, LC574 Series: 1 ns /d iv to 2 µ s /d iv

� LC564, LC584, LC684 Series: 200 ps /d iv to 1 µ s /d iv

Single Shot: fo r trans ien t and repetitive s igna ls from :

� LC334, LC534 Series: 10 ns /d iv

� LC374, LC574 Series: 1 ns /d iv , a ll channe ls ac tive

� LC564, LC584, LC684 Series: 2 ns /d iv , a ll channe ls ac tive

Peak Detect (NOT ON LC564, LC584, OR LC684 SERIES): A t

400 M S /s , peak de tec t can capture h igh-speed events as low as1 ns , w h ile s im u ltaneous ly capturing norm ally sam pled da ta .(H ow ever, w ith a reso lu tion o f 2 .5 ns there is no guarantee tha ta ll h igh-speed events less than 2 .5 ns in dura tion w ill be capturedw ith P eak D etec t.)

Sequence: T his s to res m ultip le tim e-s tam ped events in

segm ented acqu is ition m em ories .

Dead Time between Segments: 30 µ s typ ica l, 65 µ s m ax. (o r

< 30 µ s , 50 µ s m ax. on LC334, LC534, LC574, AND LC684SERIES)


��

Number of Segments Available:��

LC334A LC374A LC534A LC574A 2 to 500LC564A LC584A LC684D 2 to 1000

LC334AM, AL LC534AM, AL LC574AM, AL LC584AM LC684DM 2 to 2000LC584AL, AXL LC684DL LC684DXL 2 to 6000

�� Timebases: m a in and up to four Zoom T races

Time/Div Range: 1 ns /d iv to 1000 s /d iv

� LC564 Series: 1 ns /d iv a t 4 G S /s , and 2 ns /d iv a t 2 G S /s , to

1000 s /d iv

� LC584, LC684 Series: 500 ps /d iv a t 8 G S /s

Clock Accuracy: ≤10 ppm

� LC684 Series: <10 ppm

Interpolator Resolution: 10 ps

� LC684 Series: 5 ps

Roll Mode:� LC334, LC374, LC534, LC574 Series: fo r >500 000 po in ts :

10 to 1000 s /d iv

� LC564, LC584, LC684 Series: ranges from 500 m s/d iv to

1000 s /d iv

External Clock:� LC334, LC374, LC534, LC574 Series: ≤1 0 0 M H z (20 to

100 M H z fo r LC374 AND LC574 SERIES ) on E X T input w ith

E C L, T T L, o r zero c ross ing leve ls . O ptiona l (C K T R IG ) 50 to500 M H z rear pane l fixed-frequency c lock input.

� LC564, LC584, LC684 Series: CKTRIG option includes rear

panel fixed-frequency clock input, DC to 500 M Hz (<20 ns

rise/fall tim e)

External Reference: There is an optional (CKTRIG ) 10 M Hz rear

panel input.


��

�� Modes: N O R M A L, A U T O , S IN G LE , and S T O P .

Sources: CH1, CH2, CH3, CH4, Line, Ext, Ext/10 (Ext/5 on LC564,LC584 , AND LC684 SERIES). S lope, Level, and Coupling are unique

to each source.

Slope: P os itive , N egative

� LC564, LC584, LC684 Series: P os itive , N egative , B i-S lope

(W indow in and out)

Coupling: A C , D C , H F , LFR E J, H FR E J

Pre-trigger Recording: 0 to 100% of fu ll sca le (ad jus tab le in 1%

increm ents)

Post-trigger Delay: 0 to 10 000 d iv is ions (ad jus tab le in 0 .1 -d iv

increm ents)

Hold-off by Time: 10 ns to 20 s

� LC564, LC584, LC684 Series: 2 ns to 20 s

Holdoff by Events: 1 to 99 999 999

Internal Trigger Range: ±5 screen d iv is ions

EXT Trigger Max. Input:� LC334 Series: 10 MΩ//15 pF (LC 334A sys tem capac itance

us ing P P 002): 250 V m ax. (D C + peak A C ≤10 kH z); 50 Ω±1% : ±5 V D C (500 m W ) or 5 V rm s

� LC374, LC534, LC574 Series: 10 MΩ//11 pF (sys tem

capac itance us ing P P 005): 400 V (D C + peak A C

≤10 kH z); 50 Ω ±1% : ±5 V D C (500 m W ) or 5 V rm s

� LC564, LC584A Series: 10 MΩ//11 pF a t p robe tip (P P 005):

400 V (D C + peak A C ≤10 kH z); 50 Ω ±1% : ±5 V D C (500

m W ) or 5 V rm s

� LC684 Series: 10 MΩ//11 pF a t p robe tip (P P 005): 100 V

(D C + peak A C ≤10 kH z); 50 Ω ±3% : ±5 V D C (500 m W ) or

5 V rm s

EXT Trigger Range: ±0 .5 V w ith E X T ; ±5 V w ith E xt/10

� LC564, LC584A Series: ±1.2 V on E X T ; ±6 V w ith E xt/5

� LC684 Series: ±0 .5 V ; ±2 .5 V w ith E X T /5

Trigger Timing: T rigger D ate and T im e are lis ted in the

“M em ory S ta tus” M enu.

Trigger Comparator: T here is an op tiona l (C K T R IG ) E C L rear

pane l ou tpu t. A lte rna tive ly, the ca lib ra tor ou tpu t can prov ide atrigger ou tpu t o r a P A S S /FA IL tes t ou tpu t.


��

�� Pattern: T he osc illoscope triggers on the log ic com bination o f

five inpu ts — C H 1 , C H 2 , C H 3 , C H 4 , and E X T T rigger, w hereeach source can be de fined as “H igh ,” “Low ,” o r “D on 't C are .”T he T rigger can be de fined as the beg inn ing or end o f thespec ified pa tte rn .

Signal or Pattern Width: T he osc illoscope triggers on the w id th

betw een tw o se lec tab le lim its from 2 .5 ns to 20 s . T yp ica lly ittriggers on g litches 1 ns w ide .

� LC564, LC584, LC684 Series: T he osc illoscope triggers on

g litches as short as 600 ps or on pu lse w id ths 600 ps to 20 s .

Signal or Pattern Interval: T he osc illoscope triggers on the

in te rva l be tw een tw o se lec tab le lim its from 10 ns to 20 s .


Dropout: T he osc illoscope triggers if the input s igna l d rops ou t

fo r longer than a tim e-out from 25 ns to 20 s .


Qualified: T he osc illoscope triggers on any source on ly if a g iven

sta te (o r trans ition) has occurred on another source . (T he de laybetw een these events can be defined as a num ber o f events onthe trigger channe l o r as a tim e in terva l.)

TV: T h is a llow s se lec tion o f up to 1500 lines , and odd or even

fie lds synchron ized fo r P A L, S E C A M , N T S C , or nonstandardvideo.

Runt (LC564 LC584, AND LC684 SERIES ONLY): T he

osc illoscope triggers on pos itive or negative run ts be tw een tw ose lec tab le lim its from 600 ps to 20 s .

Slew Rate (LC564, LC584, AND LC684 SERIES ONLY): T he

osc illoscope triggers on ris ing or fa lling edges be tw een 600 psand 20 s .

Exclusion Triggering: T h is can be perfo rm ed in G litch , In te rva l,

R unt, and S lew -R ate trigger m odes. T he osc illoscope triggers onin te rm itten t fau lts by spec ifying the norm al w id th , period , leve l, o rs lew o f a s igna l. It w ill trigger on ly on aberra tions tha t a re shorte ror longer than norm al.

�� T his au tom atica lly se ts sens itiv ity, vertica l o ffse t, and tim ebase

on a ll d isp lay channe ls .

Autosetup Time: 2 to 3 seconds

Vertical Find: T h is au tom atica lly se ts sens itiv ity and o ffse t fo r

se lec ted channe l.


��

�� LC334: O ne PP005 probe is supplied per channel: DC to 350 M Hz

typical at probe tip, 500 V m ax.

LC374, LC534, LC574A, LC564, LC584, LC684 Series: O ne

PP005 probe is supplied per channel: DC to 500 M Hz typical atprobe tip, 500 V m ax.

Probe calibration: 1 V m ax. in to 1 MΩ, 500 m V in to 50 Ω;

frequency and am plitude can beprogram m ed; pu lse or square w avecan be se lec ted ; rise and fa ll tim e:1 ns typ ica l.


��

��

�� Screen Type: C o lor 10-inch R aster S can C R T , 0 .26 m m dot

p itch .

� LC684 Series: 10 .4 ” T FT -LC D

Resolution: 640 x 480 po in ts

Display Area: 170 m m x 125 m m

� LC684 Series: 212 m m X 160 m m

Controls: T here are rear pane l p resets fo r pos ition , b righ tness,

and contras t; and fron t pane l m enu contro ls fo r b righ tness andco lor se lec tion .

Grid Styles: S ing le , D ua l, Q uad, O cta l, X Y, S ing le + X Y, D ua l +

X Y, and Fu ll S creen (en la rged v iew o f each grid s tyle )

Graticules: In te rna lly genera ted , they have a separa te in tens ity

contro l fo r g rids and w aveform s, and o ffe r se lec tab le b lend ing o fgrid w ith d isp layed traces.

Waveform Style: C hoose from D ot Jo in w ith op tiona l sam ple

po in t h igh ligh t, o r D ots on ly.

Persistence Modes: C olor G raded and A na log P ers is tence;

in fin ite o r variab le w ith decay over tim e

� LC334A Series: A na log P ers is tence is ava ilab le on ly w hen

a ll four channe ls a re com bined.

Trace Display: C hoose from opaque or transparent m odes, w ith

overlap m anagem ent.

Number of Traces: 8 (any m ix o f channe ls , m em ories , o r M ath

functions)

Real-time Clock: D ate , hours , m inu tes , seconds

External Monitor: A rear pane l 15-p in socket is ava ilab le fo r

V G A com patib le m on ito r.

Vertical Zoom: up to five tim es vertica l expans ion (50 tim es w ith

averag ing , up to 40 µV /d iv sens itiv ity)

Horizontal Zoom:� LC334A, LC534A: up to 2 or 2 .5 po in ts /d iv is ion

� LC374A, LC574A: up to 0 .4 o r 0 .5 po in ts /d iv is ion

� LC564, LC584, LC684 Series: up to 0 .4 po in ts /d iv is ion


��

��

�� Microprocessor: 96 MHz PowerPC™ 603e

� LC584AXL, LC684DXL: 192 M Hz PowerPC™Video Memory: 1 M byte

Cache Memory: 32 kbytes

Persistence Data Map Memory: 16 b its per d isp layed p ixe l

(64 000 leve ls )

�� U p to four p rocess ing func tions m ay be perfo rm ed

s im ultaneous ly. S tandard func tions ava ilab le a re : A dd, S ubtrac t,M u ltip ly, D iv ide , N egate , Identity, S um m ation A verag ing and S inex/x , In tegra l, D eriva tive , S quare R oot, R atio , and A bso lu te V a lue .T he source in fo rm ation fo r a m ath func tion trace can be da tafrom an acqu is ition channe l o r from another m ath func tion trace .T his a llow s d isp lay o f traces tha t ‘da isy cha in ’ m ath func tions .

Average: up to 106 averages

Extrema: R oof, F loor, o r E nve lope va lues from 1 to 106 sw eeps

ERES: S ix low -pass d ig ita l filte rs p rov ide up to 11-b it vertica l

reso lu tion . S am pled da ta is a lw ays ava ilab le , even w hen a traceis tu rned o ff.

FFT: S pectrum A na lys is w ith five w indow ing func tions and FFT

averag ing

Resample: T h is deskew feature allows a signal to be resam pled

and adjusted in tim e relative to another signal.

Statistical Diagnostics: T he P aram eter A na lys is package

perm its in -depth d iagnostics on w aveform param eters . W ith th ispackage, live h is togram m ing o f any w aveform param eterm easurem ent is poss ib le . T he h is togram can be autosca led tod isp lay the center and w id th o f the d is tribu tion . A ny o f the aboveprocesses can be invoked w ithout los ing the data . T rend ing isa lso ava ilab le w ith th is package, w h ich is s tandard on the LC 574,LC 584, and LC 684 S eries , and optiona l on a ll o ther m ode ls .


��

�� Waveform Memory: T h is fea tures up to four 16-b it m em ories

(M 1, M 2, M 3, M 4), w hose length corresponds to the length o f thechanne l acqu is ition m em ory.

Zoom and Math Memory: U p to four 16-b it W aveform

P rocess ing M em ories (A , B , C , D ), w hose length corresponds tothe length o f the channe l acqu is ition m em ory

Setup Memory: Four non-vo la tile m em ories (op tiona l m em ory

cards , flash d isks , o r rem ovab le hard d isks m ay a lso be used fo rh igh-capac ity w aveform and se tup s to rage.)

�� Relative Time: A pa ir o f a rrow cursors m easures tim e

d iffe rences and vo ltage d iffe rences re la tive to each o ther.

Relative Voltage: A pa ir o f line cursors m easures vo ltage

d iffe rences.

Absolute Time: A c ross-ha irs m arker m easures tim e re la tive to

the trigger and vo ltage (w ith respect to g round).

Absolute Voltage: A re fe rence bar m easures vo ltage w ith

respect to g round.

�� A w ide range o f pu lse param eter m easurem ents is ava ilab le ,

ca tegorized fo r ease o f use. T he ca tegories inc lude P u lse ,H orizonta l, and V ertica l param eters . B as ic s ta tis tica lm easurem ents such as average, h ighest, low est, and s tandarddevia tion (inc luded as s tandard) can be m ade on theseparam eter m easurem ents in o rder to unders tand the ird is tribu tion .

P ass/Fa il T es ting and W aveform L im it tes ting (us ing m asks) canbe perfo rm ed. T est cond itions can be expressed as e itherw aveform param eter lim its , w aveform shape lim its (m ask ), o r acom bination o f bo th . A ny fa ilu re can cause preprogram m edactions such as H ardcopy, S ave, G P IB service request, log icpu lse out, aud ib le beep, o r a com bination o f these.


��

�� Remote Control: G P IB and R S -232-C fo r a llfron t pane l contro ls ; in te rna l func tionsRS-232-C Port: A synchronous; up to115.2 kB aud fo r com puter o r te rm ina lcontro l, p rin te r o r p lo tte r connectionGPIB Port: (IE E E -488.1) configurab le asta lker/lis tener fo r com puter contro l and fas tdata transfer; com m and language com plian t w ith IE E E -488.2Centronics Port: hardcopy in te rface

Shielded cables less than 3 m in length are required toconform to EMC Directive 89/336/EEC.PC Card (PCMCIA I/II/III Ports): op tiona l fo r m em ory cards ,flash cards , o r rem ovab le hard d isksFloppy Disk: h igh dens ity 3 .5-inch floppy d isk drive (D O Sform at)

VGA Compatible Display: 15-p in , D -type, V G A -com patib le

connector fo r ex terna l co lo r d isp lay. You m ay experienceflickering if you connect an LC D pro jec tor to the V G A outpu t.

Hardcopy: T IFF and BM P form ats available for export to Desktop

Publishing program s; HPG L protocol for vector graphics

Printers and Plotters:� B/W Printers: H P LaserJe t™ , H P D eskJet™ 500,

E pson™ FX

� Color Printers: H P D eskJet™ 550C ; E pson™ S tylus ; Canon

200, 600, 800 Series

� Plotters: HP 7470, HP 7550

� Internal: h igh-reso lu tion graph ics

�� depend ing on m ode l; s tripchart ou tpu t fo rm at w ith 2 m perd iv is ion a lso ava ilab le

Output Formats: B inary, o r A S C II w aveform outpu t com patib lew ith spreadsheets , M A T LA B™, and M athC ad™

�� Auto-calibration: Ensures specified DC and tim ing accuracyTemperature (operating): 5 to 40 °C (41 to 104 °F)Humidity (operating): ��Altitude (operating): ��°C am bient

Shock and Vibration: C onform s to se lec ted sec tions o f

M IL-P R F-28800F , C lass 3


��

Power: 90 to 132 V A C , or 180 to 250 V A C , 45 to 66 H z,

au tom atic vo ltage se lec tion , 400 W m ax. (LC684 Series: 350 W

m ax.)Battery Backup: fron t pane l se ttings m ain ta ined fo r tw o years

Dimensions: (H W D ) 10 .4 x 15 .65 x 17 .85 inches (264 x 397 x

453 m m )

Weight: 44 lb . (20 kg) ne t; 61 .6 lb (28 kg) sh ipp ing

� LC684 Series: 35 lb (16 kg) ne t, 53 lb (24 kg) sh ipp ingWarranty: 3 years

�� CE Declaration of Conformity: T he osc illoscope m eetsrequ irem ents o f E M C D irec tive 89/336/E E C for E lec trom agneticC om patib ility, and Low V o ltage D irec tive 73/23/E E C for P roductS afe ty.

� EMC: E N 50081-1 :1992 (E m iss ions); E N 50082-1 :1997

(Im m unity)

� Low Voltage Directive: C onform s to E N 61010-1 :1993 +

A m d. 2 :1995, S afe ty requ irem ents fo r e lec trica l equ ipm entfo r m easurem ent, contro l, and labora tory use .T he osc illoscope has been qua lified to the fo llow ingE N 61010-1 ca tegory:

Ins ta lla tion (O vervo ltage) C ategory IIP ollu tion D egree 2

S ee D ec lara tion o f C onform ity fo r fu rther de ta ils .

� UL and cUL Certifications: U L S tandard U L 3111-1 ; C anad ian S tandard C S A -C 22.2 N o. 1010.1-92

U L and cU L L is ting F ile : E 170588

# # #


� ��

��

The available sampling rate of LeCroy oscilloscopes is oftenhigher than that required for the analyzed signal’sbandwidth. Oversampling, particularly pronounced in thelong-memory models, can be used to increase the displayedtrace’s effective resolution: the ability of the instrument todistinguish closely spaced voltage levels. This is done byfiltering the digitized signal using Enhanced Resolution.A lthough s im ila r to s igna l sm ooth ing us ing a s im p le m oving-average filte r, enhanced reso lu tion filte ring is m ore e ffic ien t bo thin te rm s o f bandw id th and the superio r passband characteris ticstha t resu lt. A nd on w aveform s w ith s ing le-shot characteris tics , itcan be used ins tead o f success ive trace averag ing .

�� E nhanced reso lu tion filte ring im proves tw o im portan tcharacteris tics o f the osc illoscope.

R eso lu tion is im proved by a fixed am ount fo r each filte r. T h is trueincrease in reso lu tion occurs w hether o r no t the s igna l is no isy, o rw hether a s ing le-shot o r repetitive s igna l.

S igna l– to–no ise ra tio (S N R ) is im proved in such a w ay as to bedependent on the fo rm o f the no ise in the orig ina l s igna l. T h is isbecause the enhanced reso lu tion filte ring decreases thebandw id th o f the s igna l, there fore filte ring out som e o f the no ise .

�� T he osc illoscope ’s se t o f constan t-phase, F IR (F in ite Im pu lse-R esponse filte rs p rov ide fas t com puta tion , exce llen t s tepresponse in 0 .5 b it s teps , and m in im um bandw id th reduction fo rreso lu tion im provem ents o f be tw een 0 .5 and 3 b its . E ach s tepcorresponds to a bandw id th reduction o f a fac tor o f tw o, a llow ingeasy contro l o f the bandw id th /reso lu tion trade-o ff. T heparam eters o f the s ix filte rs a re g iven in the fo llow ing tab le :


��

��

Resolution Increase(Enhancement)

–3 dB Bandwidth(× Nyquist)

Filter Length(Samples)

0.5 0.5 21.0 0.241 51.5 0.121 102.0 0.058 242.5 0.029 513.0 0.016 117

W ith low -pass filte rs , the ac tua l S N R increase ob ta ined in anyparticu la r s itua tion depends on the pow er spectra l dens ity o f theno ise on the s igna l. T he im provem ent in S N R corresponds to theim provem ent in reso lu tion if the no ise in the s igna l is w h ite —that is , if it is even ly d is tribu ted across the frequency spectrum . Ifthe no ise pow er is b iased tow ards h igh frequenc ies , the S N Rim provem ent w ill be be tte r than the reso lu tion im provem ent.W hereas the oppos ite m ay be true if the no ise is m ostly a t low erfrequenc ies .

S N R im provem ent due to the rem ova l o f coherent no ise s igna ls— feed-th rough o f c lock s igna ls , fo r exam ple — is dec ided by thefa ll o f the dom inant frequency com ponents o f the s igna l in thepassband. T h is is eas ily ascerta ined us ing S pectra l A na lys is .

T he filte rs have a prec ise ly constan t zero phase response. T h ishas tw o des irab le p roperties . F irs t, the filte rs do no t d is to rt there la tive pos ition o f d iffe ren t events in the w aveform , even if theevents ’ frequency conten t is d iffe ren t. A nd second, because thew aveform s are s to red , the de lay norm ally assoc ia ted w ith filte ring(betw een the input and ou tpu t w aveform s) can be exactlycom pensated during the com puta tion o f the filte red w aveform .

A ll the filte rs have been g iven exact un ity ga in a t low frequency.E nhanced reso lu tion shou ld thus no t cause overflow if the sourcedata is no t overflow ed. If part o f the source trace w ere tooverflow , filte ring w ou ld be a llow ed, bu t the resu lts in the v ic in ityo f the overflow ed data — the filte r im pu lse response length —


��

w ould be incorrec t. T h is is because in som e c ircum stances anoverflow m ay be a sp ike o f on ly one or tw o sam ples , and theenergy in th is sp ike m ay not be enough to s ign ificantly a ffec t theresu lts . It w ou ld then not be des irab le to d isa llow the w ho le trace.

�� In genera l, enhanced reso lu tion is used to rep lace the averag ingfunction in s itua tions w here the da ta record has a s ing le -shot o rs low ly repetitive na ture and averag ing cannot be used.

T here are tw o particu la r s itua tions in w h ich enhanced reso lu tionis espec ia lly use fu l. O ne is w hen the s igna l is no ticeab ly no isyand m easurem ents o f the no ise are no t requ ired . T he s igna l canbe “c leaned up” by us ing the enhanced reso lu tion func tion . T heother is w hen — even if the s igna l is no t particu la rly no isy —high-prec is ion m easurem ents o f the w aveform are requ ired(w hen us ing E xpand w ith h igh vertica l ga in , fo r exam ple).E nhanced reso lu tion w ill then increase the reso lu tion o f them easurem ents .

T he exam ples on the fo llow ing pages illus tra te how enhancedreso lu tion can be used.


��

��

�� This screen shows the spectrum of a square signal before (top grid)and after (bottom grid) enhanced resolution processing. The resultclearly illustrates how the filter rejects high-frequency com ponentsfrom the signal. The higher the bit enhancem ent, the lower theresulting bandwidth.


��

�� In this exam ple the bottom trace has been significantly enhanced by

a 3-bit enhanced resolution function.

�� The original signal being highly oversampled, theresulting bandwidth is still high enough for the signal not tobe distorted.


��

�� This illustration shows the effect of enhanced resolution on a noisysignal. The original trace (top grid) has been processed by a 2-bitenhanced resolution filter. The result (bottom grid) shows a “sm ooth”trace, where m ost of the noise has been elim inated.


��

# # #

��

� The enhanced resolution function can only improve the resolution of a trace; it cannotimprove the accuracy or linearity of the original quantization by the 8-bit ADC.

� The constraint of good temporal response excludes the use of maximally flat filters.The pass band will therefore cause signal attenuation for signals near the cut-offfrequency. The highest frequencies passed may be slightly attenuated. The frequencyresponse of a typical enhanced resolution filter (the 2-bit enhancement filter) isillustrated below, indicating the –3 dB cut-off frequency of 5.8% of the Nyquistfrequency.

� The filtering must be performed on finite record lengths: data will be lost at the startand end of the waveform, so that the trace becomes slightly shorter after filtering.

� The number of samples lost is exactly equal to the length of the impulse response ofthe filter used. It thus varies between two and 117 samples. Because of theoscilloscope’s very long waveform memories, this loss — just 0.2% of a 50 000 pointtrace — is not normally noticed. However, it is possible to demand filtering on a recordso short, there would be no data output. In this case the scope will not allow filtering.


��

BLANK PAG E


��

��

The WP02 Spectral Analysis package with FFT (Fast FourierTransform) reveals signal characteristics not visible in thetime domain, and adds the power of frequency domainanalysis to your oscilloscope. FFT converts a time domainwaveform into frequency domain spectra similar to those ofa spectrum analyzer, but with important differences andadded benefits.

�� For a la rge c lass o f s igna ls , g rea ter ins igh t can be ga ined by

look ing a t spectra l representa tion ra ther than tim e descrip tion .S igna ls encountered in the frequency response o f am plifie rs ,osc illa to r phase no ise and those in m echan ica l v ib ra tion ana lys is— to m ention jus t som e app lica tions — are eas ie r to observe inthe frequency dom ain .

If sam pling is done a t a ra te fas t enough to fa ith fu lly approx im ate

the orig ina l w aveform (usua lly five tim es the h ighest frequency

com ponent in the s igna l), the resu lting d iscre te da ta series w ill

un ique ly describe the ana log s igna l.

T h is is o f particu la r va lue w hen dea ling w ith trans ien t s igna lsbecause, un like FFT , conventiona l sw ept spectrum ana lyzerscannot hand le them .

�� S pectra l ana lys is theory assum es tha t the s igna l fo rtrans form ation be o f in fin ite dura tion . S ince no phys ica l s igna lcan m eet th is cond ition , a use fu l assum ption fo r reconc ilingtheory and prac tice is to v iew the s igna l as cons is ting o f anin fin ite series o f rep lica o f itse lf. T hese rep lica are m u ltip lied by arec tangu lar w indow (the d isp lay grid ) tha t is zero ou ts ide o f theobserva tion grid .

� For an explanation of FFT terms: see the Glossaryon page C–17

� Using FFT Functions: see page C–9� FFT Algorithms: page C–14


��

F igure C –1 show s spectra o f a sw ept triangu lar w ave.D iscontinu ities a t the edges o f the w ave produce leakage, aneffec t c learly v is ib le in T race A , w h ich w as com puted w ith arec tangu lar w indow , bu t less pronounced in the V on H annw indow in T race B (see be low fo r exp lanations o f leakage andw indow types). H is togram m ing in T race C tracks the spread o fthe firs t harm on ic .

Figure C–1

S lic ing the w aveform in th is m anner is like d ilu ting the spectra lenergy in an in fin ite num ber o f s ide lobes, w h ich correspond tom ultip les o f the frequency reso lu tion Δf (F ig . C –2). T heobserva tion w indow or capture tim e T de term ines the frequencyreso lu tion o f the FFT (Δf=1 /T ). W hereas the sam pling period andthe record length se t the m ax im um frequency span tha t can beobta ined (fN yq=Δf*N /2).


��

Figure C–2

A n FFT opera tion on an N -po in t tim e dom ain s igna l m ay thus becom pared to pass ing the s igna l th rough a com b filte r cons is tingof a bank o f N /2 filte rs . A ll the filte rs have the sam e shape andw id th and are centered a t N /2 d iscre te frequenc ies . E ach filte rco llec ts the s igna l energy tha t fa lls in to the im m edia tene ighborhood o f its center frequency. T hus it can be sa id tha tthere are N /2 frequency b ins . T he d is tance in H z be tw een thecenter frequenc ies o f tw o ne ighboring b ins is a lw ays the sam e:Δf.

�� B ecause o f the linear sca le used to show m agn itudes, low eram plitude com ponents a re o ften h idden by la rger com ponents . Inadd ition to the func tions o ffe ring m agn itude and phaserepresenta tions , the FFT option o ffe rs pow er dens ity and pow erspectrum dens ity func tions , se lec ted from the “FFT resu lt” m enushow n in the figures . T hese la tte r func tions are even bette rsu ited fo r charac terizing spectra . T he pow er spectrum (V

2) is the

square o f the m agn itude spectrum (0 dB m corresponds tovo ltage equ iva len t to 1 m W in to 50 Ω.) T h is is the representa tion


��

of cho ice fo r s igna ls conta in ing iso la ted peaks — period ics igna ls , fo r ins tance.

T he pow er dens ity spectrum (V2/H z) is the pow er spectrum

div ided by the equ iva len t no ise bandw id th o f the filte r in H zassoc ia ted w ith the FFT ca lcu la tion . T h is is bes t em ployed fo rcharac terizing broadband s igna ls such as no ise .

�� T he am ount o f acqu is ition m em ory ava ilab le w ill de term ine them ax im um range (N yqu is t frequency) over w h ich s igna lcom ponents can be observed. C ons ider the prob lem o fdeterm in ing the length o f the observation w indow and the s ize o fthe acqu is ition buffe r if a N yqu is t ra te o f 500 M H z and areso lu tion o f 10 kH z are requ ired . T o obta in a reso lu tion o f 10kH z, the acqu is ition tim e m ust be a t leas t:

T = 1 /Δf = 1 /10 kH z = 100 µs .

For a d ig ita l osc illoscope w ith a m em ory o f 100 kB , the h ighestfrequency tha t can be ana lyzed is :

Δf × N /2 = 10 kH z × 100 kB /2 = 500 M H z.

�� T ake care to ensure tha t s igna ls a re correc tly acqu ired : im properw aveform pos ition ing w ith in the observa tion w indow produces ad is to rted spectrum . T he m ost com m on d is to rtions can be tracedto insu ffic ien t sam pling , edge d iscontinu ities , w indow ing or the“p icke t fence” e ffec t.

B ecause the FFT ac ts like a bank o f bandpass filte rs centered a tm ultip les o f the frequency reso lu tion , com ponents tha t a re no texact m u ltip les o f tha t frequency w ill fa ll w ith in tw o consecutivefilte rs . T h is resu lts in an a ttenuation o f the true am plitude o fthese com ponents .

�� T he h ighest po in t in the spectrum can be 3 .92 dB low er w hen the

source frequency is ha lfw ay be tw een tw o d iscre te frequenc ies .T h is varia tion in spectrum m agn itude is the p icke t fence e ffec t.T he correspond ing a ttenuation loss is re fe rred to as sca llop loss .LeC roy scopes au tom atica lly correc t fo r the sca llop e ffec t,ensuring tha t the m agn itude o f the spectra lines correspond tothe ir true va lues in the tim e dom ain .


��

If a s igna l conta ins a frequency com ponent above N yqu is t, thespectrum w ill be a liased, m ean ing tha t the frequenc ies w ill befo lded back and spurious . S potting a liased frequenc ies is o ftend ifficu lt, as the a liases m ay ride on top o f rea l harm on ics . As im p le w ay o f check ing is to m od ify the sam ple ra te and observew hether the frequency d is tribu tion changes.

�� FFT assum es tha t the s igna l conta ined w ith in the tim e grid isrep lica ted end less ly ou ts ide the observa tion w indow . T here fore ifthe s igna l conta ins d iscontinu ities a t its edges, pseudo-frequenc ies w ill appear in the spectra l dom ain , d is to rting the rea lspectrum . W hen the s ta rt and end phase o f the s igna l d iffe r, thes igna l frequency fa lls w ith in tw o frequency ce lls b roaden ing thespectrum .

T his e ffec t is illus tra ted in F igure C –1. B ecause the d isp lay doesnot conta in an in tegra l num ber o f periods , the spectrumdisp layed in T race B does no t revea l sharp frequencycom ponents . In te rm ed ia te com ponents exh ib it a low er andbroader peak . T he broaden ing o f the base, s tre tch ing ou t inm any ne ighboring b ins , is te rm ed leakage. C ures fo r th is a re toensure tha t an in tegra l num ber o f periods is conta ined w ith in thed isp lay grid o r tha t no d iscontinu ities appear a t the edges.A nother is to use a w indow function to sm ooth the edges o f thes igna l.

�� T he cho ice o f a spectra l w indow is d ic ta ted by the s igna l’scharac teris tics . W eighting func tions contro l the filte r responseshape, and a ffec t no ise bandw id th as w e ll as s ide lobe leve ls .Idea lly, the m ain lobe shou ld be as narrow and fla t as poss ib le toe ffec tive ly d iscrim ina te a ll spec tra l com ponents , w h ile a ll s idelobes shou ld be in fin ite ly a ttenuated.

C hosen from the “w ith w indow ” m enu, the w indow type de finesthe bandw id th and shape o f the equ iva len t filte r to be used in theFFT process ing .

In the sam e w ay as one w ou ld choose a particu la r cam era lensfo r tak ing a p ic tu re , som e experim enting is genera lly necessaryto de term ine w h ich w indow is m ost su itab le . H ow ever, thefo llow ing genera l gu ide lines shou ld he lp (see page C –11 fo rw indow types).


��

R ectangu lar w indow s prov ide the h ighest frequency reso lu tionand are thus usefu l fo r es tim ating the type o f harm on ics presentin the s igna l. B ecause the rec tangu lar w indow decays as a s inx /xfunction in the spectra l dom ain , s ligh t a ttenuation w ill be induced.A lte rna tive func tions w ith less a ttenuation — F la ttop andB lackm an-H arris — provide m ax im um am plitude a t the expenseof frequency reso lu tion . W hereas, H am m ing and von H ann aregood fo r genera l purpose use w ith continuous w aveform s.

�� E nhanced reso lu tion (see A ppend ix B ) uses a low pass filte ring

techn ique tha t can potentia lly p rovide fo r th ree add itiona l b its(18 dB ) if the s igna l no ise is un ifo rm ly d is tribu ted (w h ite ). Lowpass filte ring shou ld be cons idered w hen h igh frequencycom ponents are irre levant. A d is tinc t advantage o f th is techn iqueis tha t it w orks fo r bo th repetitive and trans ien t s igna ls . T he S N Rincrease is cond itioned by the cu t-o ff frequency o f the E res lowpass filte r and the no ise shape (frequency d is tribu tion).

LeC roy d ig ita l osc illoscopes em ploy F IR d ig ita l filte rs so tha t aconstant phase sh ift is m ain ta ined. T he phase in form ation isthere fore not d is to rted by the filte ring ac tion .

�� E ven greater dynam ic-range im provem ent is ob ta ined on s igna ls

show ing period ic ity. M oreover, the range can be increasedw ithout sacrific ing frequency response. T he LeC roy osc illoscopebe ing used is equ ipped w ith accum ula tion buffe rs 32 b its w ide toprevent overflow s.

S pectra l pow er averag ing is usefu l w hen the s igna l varies in tim eand the m ean pow er o f the s igna l needs to be es tim ated. T yp ica lapp lica tions inc lude no ise and pseudo-random no ise . W hereastim e averag ing ignores phase in form ation , spectra l averag ingtracks m agn itude as w e ll as phase in form ation . It is thus asuperio r es tim ator. T he im provem ent is typ ica lly p roportiona l tothe square roo t o f the num ber o f averages. For ins tance,averag ing w h ite no ise a t fu ll sca le over 10 sw eeps yie lds a typ ica lim provem ent o f nearly 20 dB .


��

S pectra l pow er averag ing is the techn ique to use w hen you aredeterm in ing the frequency response o f pass ive ne tw orks such asfilte rs . F igures 3 and 4 show the trans fer func tions o f a low passfilte r w ith a 3 -dB cu to ff o f 11 M H z, ob ta ined by exc iting the filte rw ith a w h ite no ise source (F ig . C –3) and a s ine sw ept genera tor(F ig . C –4). B oth techn iques g ive substan tia lly the sam e resu lts .T he cho ice o f m ethod is governed by the ava ilab ility o f anadequate genera ting source .

T he spectra o f s ing le tim e-dom ain w aveform s can be com putedand d isp layed to ob ta in pow er averages ob ta ined over as m anyas 50 000 spectra .

Figure C–3


��

Figure C–4

�� B ecause o f its versa tility, FFT ana lys is has becom e a popu lar

ana lys is too l. H ow ever, som e care m ust be taken w ith it. In m ostins tances, incorrec t pos ition ing o f the s igna l w ith in the d isp laygrid w ill s ign ificantly a lte r the spectrum . E ffec ts such as leakageand a lias ing tha t d is to rt the spectrum m ust be unders tood ifm ean ingfu l conc lus ions are to be arrived a t w hen us ing FFT .

A n e ffec tive w ay to reduce these e ffec ts is to m ax im ize theacqu is ition record length . R ecord length d irec tly cond itions theeffec tive sam pling ra te o f the scope and there fore determ ines thefrequency reso lu tion and span a t w h ich spectra l ana lys is can becarried out.


��

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Select “FFT” from the “Math Type” menu (see Chapter 10for a full description of math and waveform processingmenus). Spectra displayed with a linear frequency axisrunning from zero to the Nyquist frequency are shown at theright-hand edge of the trace. The frequency scale factors(Hz/div) are in a 1–2–5 sequence.T he process ing equation is d isp layed a t the bo ttom o f the screen,together w ith the th ree key param eters tha t charac te rize an FFTspectrum . T hese are :

• trans form s ize N (num ber o f input po in ts )

• N yqu is t frequency (= ½ sam ple ra te )

• frequency increm ent Δf be tw een tw o success ive po in ts o f thespectrum

T hese param eters a re re la ted by

N yqu is t frequency = Δf ∗ N /2

W here : Δf = 1 /T , and w here T is the dura tion o f the inputw aveform record (10 ∗ tim e/d iv). T he num ber o f ou tpu t po in ts isequa l to N /2 .

�� FFT spectra are computedover the entire source time-domain waveform. This limitsthe number of points used for FFT processing. If theinput waveform contains more points than the selectedmaximum in “for Math use max points,” they aredecimated before FFT processing. But if it has fewer, allpoints are used.


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T he fo llow ing se lec tions can be m ade us ing the “FFT resu lt”m enu.

��

T his is m easured w ith respect to a cos ine w hose m ax im umoccurs a t the le ft-hand edge o f the screen, a t w h ich po in t it has0°. S im ila rly, a pos itive-go ing s ine s ta rting a t the le ft-hand edgeof the screen has a –90° phase (d isp layed in degrees).

��

T his is the s igna l pow er norm alized to the bandw id th o f theequ iva len t filte r assoc ia ted w ith the FFT ca lcu la tion . T he pow erdens ity is su itab le fo r charac terizing broadband no ise . (It isd isp layed on a logarithm ic vertica l ax is ca lib ra ted in dB m .)

��

T his is the s igna l pow er (o r m agn itude) represented on alogarithm ic vertica l sca le : 0 dB m corresponds to the vo ltage(0 .316 V peak ), w h ich is equ iva len t to 1 m W in to 50 Ω. T hepow er spectrum is su itab le fo r charac terizing spectra tha t conta iniso la ted peaks (dB m ).

��

T his is the peak s igna l am plitude represented on a linear sca le .(It has the sam e un its as the input s igna l.)

��

T hese represent the com plex resu lt o f the FFT process ing . (T heyhave the sam e un its as the input s igna l.)


��

�� Chosen using the “w ith w indow” m enu, the window type defines thebandwidth and shape of the filter to be used in the FFT processing(see the tab le on page C –17 fo r these filte rs ’ param eters). W hen“A C ” is se lec ted from the sam e m enu, the D C com ponent o f theinput s igna l is fo rced to zero prio r to the FFT process ing . T h isim proves the am plitude reso lu tion , espec ia lly w hen the input hasa la rge D C com ponent.

Window Type Applications and Limitations

Rectangular

These are norm ally used when the signal is transient (com pletely

contained in the tim e-dom ain w indow) or known to have a

fundam ental frequency com ponent that is an integer m ultiple of the

fundam ental frequency of the w indow. S ignals other than these

types w ill show varying am ounts of spectral leakage and scallop

loss, which can be corrected by selecting another type of w indow.

Hanning (Von Hann) These reduce leakage and im prove am plitude accuracy. However,

frequency resolution is also reduced.

Hamming These reduce leakage and im prove am plitude accuracy. However,

frequency resolution is also reduced.

Flat Top This w indow provides excellent am plitude accuracy w ith m oderate

reduction of leakage, but w ith reduced frequency resolution.

Blackman–Harris It reduces the leakage to a m inim um , but w ith reduced frequency

resolution.

�� A function can be de fined as the pow er average of FFT spectracom puted by another func tion (see page C –6). C hoose“FFT A V G ” from the “M ath T ype” m enu, and “P ow er S pect” from“FFT R esu lt.”


��

�� O ther w aveform process ing func tions , such as A verag ing andA rithm etic , can be app lied to w aveform s before FFT process ingis perfo rm ed. T im e-dom ain averag ing prio r to FFT , fo r exam ple ,can be used if a s tab le trigger is ava ilab le to reduce randomnoise in the s igna l.

�� W hen FFT is used, the fie ld beneath the grid � d isp laysparam eters o f the w aveform descrip to r, inc lud ing num ber o fpo in ts , horizonta l and vertica l sca le fac tors , and un its .

�� For reading the am plitude and frequency of a data point, theAbsolute T im e cursor can be m oved into the frequency dom ain bygoing beyond the right-hand edge of a tim e-dom ain waveform .

T he R e la tive T im e cursors can be m oved in to the frequencydom ain to s im u ltaneous ly ind ica te the frequency d iffe rence andthe am plitude d iffe rence be tw een tw o po in ts on each frequency-dom ain trace .

T he A bso lu te V o ltage cursor reads the abso lu te va lue o f a po in tin a spectrum in the appropria te un its , and the R e la tive V o ltagecursors ind ica te the d iffe rence be tw een tw o leve ls on each trace

��

� To increase the FFT frequency range, the Nyquistfrequency, raise the effective sampling frequency byincreasing the maximum number of points or using afaster time base.

� To increase the FFT frequency resolution, increase thelength of the time-domain waveform record by using aslower time base.


��

�� O ne o f these FFT -re la ted erro r m essages m ay be d isp layed a t

the top o f the screen.

��

Message Meaning“Incompatible input record type” FFT pow er average is de fined on ly on a func tion de fined

as FFT .

“Horizontal units don't match” FFT o f a frequency-dom ain w aveform is no t ava ilab le .

“FFT source data zero filled” If there are inva lid da ta po in ts in the source w aveform (a tthe beg inn ing or a t the end o f the record), these arerep laced by zeros be fore FFT process ing .

“FFT source data over/underflow” T he source w aveform data has been c lipped inam plitude, e ither in the acqu is ition — ga in too h igh orinappropria te o ffse t — or in p rev ious process ing . T heresu lting FFT conta ins harm on ic com ponents w h ichw ou ld no t be present in the unc lipped w aveform . T hesettings de fin ing the acqu is ition or p rocess ing shou ld bechanged to e lim ina te the over/underflow cond ition .

“Circular computation” A function defin ition is c ircu la r (i.e . the func tion is its ow nsource, ind irec tly v ia another function or expans ion).O ne o f the defin itions shou ld be changed.


��

��

A summary of the algorithms used in the oscilloscope’s FFTcomputation is given here in the form of seven steps:

1. If the m ax im um num ber o f po in ts is sm alle r than the sourcenum ber o f po in ts , the source w aveform data are dec im atedprio r to the FFT . T hese dec im ated da ta ex tend over the fu llleng th o f the source w aveform . T he resu lting sam plingin te rva l and the ac tua l trans form s ize se lec ted prov ide thefrequency sca le fac tor in a 1–2–5 sequence.

2 . T he da ta are m ultip lied by the se lec ted w indow function .

3 . FFT is com puted, us ing a fas t im p lem enta tion o f the D FT(D iscre te Fourie r T ransform ):

XN

x Wn kn k

k

k N

= ×=

= −

∑1

0

1

w here : xk is a com plex array w hose rea l part is the m odifiedsource tim e dom ain w aveform , and w hose im ag inary part is0 ; X n is the resu lting com plex frequency-dom ain w aveform ;

W e j N= −2π / ; and N is the num ber o f po in ts in xk and X n.

T he genera lized FFT a lgorithm , as im p lem ented here , w orkson N , w h ich need not be a pow er o f 2 .

4 . T he resu lting com plex vec tor X n is d iv ided by the coherentga in o f the w indow function , in o rder to com pensate fo r theloss o f the s igna l energy due to w indow ing. T h iscom pensation provides accura te am plitude va lues fo riso la ted spectrum peaks.

5 . T he rea l part o f X n is sym m etric a round the N yqu is tfrequency, tha t is

R n = R N -n

w hile the im ag inary part is asym m etric , tha t is

In = – IN -n


��

T he energy o f the s igna l a t a frequency n is d is tribu ted equa llybetw een the firs t and the second ha lves o f the spectrum ; theenergy a t frequency 0 is com ple te ly conta ined in the 0 te rm .

T he firs t ha lf o f the spectrum (R e, Im ), from 0 to the N yqu is tfrequency is kept fo r fu rther p rocess ing and doub led inam plitude:

R ’n = 2 x R n 0 ≤ n < N /2

I’n = 2 x In 0 ≤ n < N /2

6. T he resu ltan t w aveform is com puted fo r the spectrum typese lec ted .

If “R ea l,” “Im ag inary,” or “R ea l + Im ag inary” is se lec ted, nofurther com puta tion is needed. T he appropria te part o f thecom plex resu lt is g iven as the resu lt (R ’n o r I’n o r R ’n + jI’n , asdefined above).

If “M agn itude” is se lec ted , the m agn itude o f the com plexvector is com puted as :

M R In n n= +’ ’2 2

S teps 1–6 lead to the fo llow ing resu lt:

A n A C s ine w ave o f am plitude 1 .0 V w ith an in tegra l num ber o fperiods N p in the tim e w indow , trans form ed w ith the rec tangu larw indow , resu lts in a fundam enta l peak o f 1 .0 V m agn itude in thespectrum a t frequency N p × Δf. H ow ever, a D C com ponent o f 1 .0V , trans form ed w ith the rec tangu lar w indow , resu lts in a peak o f2 .0 V m agn itude a t 0 H z.

T he w aveform s fo r the o ther ava ilab le spectrum types arecom puted as fo llow s:

P hase: ang le = arc tan (In/R n) M n > M m in

ang le = 0 M n ≤ M m in


��

W here M m in is the m in im um m agn itude, fixed a t about 0 .001 o fthe fu ll sca le a t any ga in se tting , be low w h ich the ang le is no t w e llde fined.

T he dB m P ow er S pectrum :

dBm PSM

M

M

M

n

ref

n

re f

= ×⎛

⎝⎜⎜

⎞

⎠⎟⎟ = ×

⎛

⎝⎜

⎞

⎠⎟10 2010

2

2 10log log

w here M ref = 0 .316 V (tha t is , 0 dB m is de fined as a s ine w ave o f

0 .316 V peak or 0 .224 V R M S , g iv ing 1 .0 m W in to 50Ω).

T he dB m P ow er S pectrum is the sam e as dB m M agn itude, assuggested in the above fo rm ula .

dB m P ow er D ens ity:

( )dBm PD dBm P S EN B W f= − × ×10 10log Δ

w here E N B W is the equ iva len t no ise bandw id th o f the filte rcorrespond ing to the se lec ted w indow , and Δ f is the currentfrequency reso lu tion (b in w id th).

7 . T he FFT P ow er A verage takes the com plex frequency-dom ain data R ’n and I’n fo r each spectrum genera ted in S tep5, and com putes the square o f the m agn itude:

M n2 = R ’n

2 + I’n2,

then sum s M n2 and counts the accum ula ted spectra . T he

to ta l is norm alized by the num ber o f spectra and converted tothe se lec ted resu lt type us ing the sam e fo rm ulas as are usedfor the Fourie r T ransform .


��

��

This section defines the terms frequently used in FFTspectrum analysis and relates them to the oscilloscope.

�� If the input s igna l to a sam pling acqu is ition sys tem conta inscom ponents w hose frequency is g rea ter than the N yqu is tfrequency (ha lf the sam pling frequency), there w ill be less thantw o sam ples per s igna l period . T he resu lt is tha t the contribu tionof these com ponents to the sam pled w aveform isind is tingu ishab le from tha t o f com ponents be low the N yqu is tfrequency. T h is is aliasing.

T he tim ebase and trans form s ize shou ld be se lec ted so tha t theresu lting N yqu is t frequency is h igher than the h ighest s ign ifican tcom ponent in the tim e-dom ain record .

�� T he norm alized coherent ga in o f a filte r correspond ing to eachw indow function is 1 .0 (0 dB ) fo r a rec tangu lar w indow and lessthan 1 .0 fo r o ther w indow s. It de fines the loss o f s igna l energydue to the m ultip lica tion by the w indow func tion . T h is loss iscom pensated fo r in the osc illoscope. T he fo llow ing tab le lis ts theva lues fo r the im p lem ented w indow s.

��

Window TypeHighest Side

Lobe(dB)

Scallop Loss(dB)

ENBW(bins)

Coherent Gain(dB)

Rectangular –13 3.92 1 .0 0 .0

von Hann –32 1 .42 1 .5 – 6 .02

Hamming –43 1 .78 1 .37 –5 .35

Flat Top –44 0 .01 2 .96 –11 .05

Blackman–Harris –67 1 .13 1 .71 –7 .53


��

�� E quiva len t N o ise B andW idth (E N B W ) is the bandw id th o f arec tangu lar filte r (sam e ga in a t the center frequency), equ iva len tto a filte r assoc ia ted w ith each frequency b in , w h ich w ou ld co llec tthe sam e pow er from a w h ite no ise s igna l. In the tab le on theprevious page, the E N B W is lis ted fo r each w indow functionim plem ented, g iven in b ins .

�� C om puting an N -po in t FFT is equ iva len t to pass ing the tim e-dom ain input s igna l th rough N /2 filte rs and p lo tting the ir ou tpu tsaga ins t the frequency. T he spac ing o f filte rs is Δf = 1 /T , w h ile thebandw id th depends on the w indow function used (see F requencyb ins).

�� T he FFT a lgorithm takes a d iscre te source w aveform , de finedover N po in ts , and com putes N com plex Fourie r coeffic ien ts ,w h ich are in te rpre ted as harm on ic com ponents o f the inputs igna l.

For a rea l source w aveform (im ag inary part equa ls 0 ), there areon ly N /2 independent harm on ic com ponents .

A n FFT corresponds to ana lyzing the input s igna l w ith a bank o fN /2 filte rs , a ll hav ing the sam e shape and w id th , and centered a tN /2 d iscre te frequenc ies . E ach filte r co llec ts the s igna l energytha t fa lls in to the im m edia te ne ighborhood o f its centerfrequency. T hus it can be sa id tha t there are N /2 “frequencyb ins .”

T he d is tance in hertz be tw een the center frequenc ies o f tw one ighboring b ins is a lw ays :

Δf = 1 /T

w here T is the dura tion o f the tim e-dom ain record in seconds.

T he w id th o f the m ain lobe o f the filte r centered a t each b independs on the w indow function used. T he rec tangu lar w indowhas a nom ina l w id th a t 1 .0 b in . O ther w indow s have w ider m a inlobes (see tab le ).

�� T he range o f frequenc ies com puted and d isp layed is 0 H z(d isp layed a t the le ft-hand edge o f the screen) to the N yqu is tfrequency (a t the righ tm ost edge o f the trace).


��

�� In a s im p le sense, the frequency reso lu tion is equa l to the b inw id th Δf. T hat is , if the input s igna l changes its frequency by Δf,the correspond ing spectrum peak w ill be d isp laced by Δf. Forsm alle r changes o f frequency, on ly the shape o f the peak w illchange.

H ow ever, the e ffec tive frequency reso lu tion (tha t is , the ab ility toreso lve tw o s igna ls w hose frequenc ies are a lm ost the sam e) isfu rther lim ited by the use o f w indow functions . T he E N B W va lueof a ll w indow s o ther than the rec tangu lar is g rea ter than Δf andthe b in w id th . T he tab le on page C –17 lis ts the E N B W va lues fo rthe im p lem ented w indow s.

�� In the pow er spectrum o f a s ine w ave w ith an in tegra l num ber o fperiods in the (rec tangu lar) tim e w indow (tha t is , the sourcefrequency equa ls one o f the b in frequenc ies), the spectrumconta ins a sharp com ponent w hose va lue accura te ly re flec ts thesource w aveform 's am plitude. For in te rm ed ia te input frequenc iesth is spectra l com ponent has a low er and broader peak .

T he broaden ing o f the base o f the peak , s tre tch ing ou t in to m anyne ighboring b ins is te rm ed leakage . It is due to the re la tive ly h ighs ide lobes o f the filte r assoc ia ted w ith each frequency b in .

T he filte r s ide lobes and the resu lting leakage are reduced w henone o f the ava ilab le w indow func tions is app lied . T he bes treduction is p rov ided by the B lackm an–H arris and F la t T opw indow s. H ow ever, th is reduction is o ffse t by a broaden ing o f them ain lobe o f the filte r.

�� FFT is com puted over the num ber o f po in ts (T ransform S ize)w hose upper bounds are the source num ber o f po in ts , and by them ax im um num ber o f po in ts se lec ted in the m enu. FFT genera tesspectra o f N /2 ou tpu t po in ts .

�� T he N yqu is t frequency is equa l to one ha lf o f the e ffec tivesam pling frequency (a fte r the dec im ation): Δf × N /2 .

�� If a s ine w ave has a w ho le num ber o f periods in the tim e dom ainrecord , the pow er spectrum obta ined w ith a rec tangu lar w indoww ill have a sharp peak , correspond ing exactly to the frequencyand am plitude o f the s ine w ave. O therw ise the spectrum peakw ith a rec tangu lar w indow w ill be low er and broader.

T he h ighest po in t in the pow er spectrum can be 3 .92 dB low er(1 .57 tim es) w hen the source frequency is ha lfw ay be tw een tw o


��

d iscre te b in frequenc ies . T h is varia tion o f the spectrumm agnitude is ca lled the p icke t fence e ffec t (the loss is ca lled thesca llop loss).

A ll w indow functions com pensate fo r th is loss to som e ex ten t, bu tthe best com pensation is ob ta ined w ith the F la t T op w indow .

�� T he pow er spectrum (V 2) is the square o f the m agn itudespectrum .

T he pow er spectrum is d isp layed on the dB m sca le , w ith 0 dB mcorrespond ing to :

V re f2 = (0 .316 V peak )2,

w here V re f is the peak va lue o f the s inuso ida l vo ltage, w h ich isequ iva len t to 1 m W in to 50 Ω.

�� T he pow er dens ity spectrum (V 2/H z) is the pow er spectrumdiv ided by the equ iva len t no ise bandw id th o f the filte r, in hertz.T he pow er dens ity spectrum is d isp layed on the dB m sca le , w ith0 dB m correspond ing to (V re f2/H z).

�� T he tim e-dom ain records are acqu ired a t sam pling frequenc iesdependent on the se lec ted tim e base. B efore the FFTcom puta tion , the tim e-dom ain record m ay be dec im ated. If these lec ted m ax im um num ber o f po in ts is low er than the sourcenum ber o f po in ts , the e ffec tive sam pling frequency is reduced.T he e ffec tive sam pling frequency equa ls tw ice the N yqu is tfrequency.

�� T his is loss assoc ia ted w ith the p icke t fence e ffec t.

�� A ll ava ilab le w indow functions be long to the sum of cos inesfam ily w ith one to th ree non-zero cos ine te rm s:

W ak

Nm k Nk m

m

m M

=⎛⎝⎜

⎞⎠⎟ ≤ <

=

= −

∑0

12

0cosp

w here : M = 3 is the m ax im um num ber o f te rm s, am are thecoeffic ien ts o f the te rm s, N is the num ber o f po in ts o f thedec im ated source w aveform , and k is the tim e index.


��

T he fo llow ing tab le lis ts the coeffic ien ts am . T he w indowfunctions seen in the tim e dom ain are sym m etric a round thepo in t k = N /2 .

��

Window Type a0 a1 a2

Rectangular 1.0 0 .0 0 .0

von Hann 0.5 –0.5 0 .0

Hamming 0.54 –0 .46 0 .0

Flat-Top 0 .281 –0 .521 0 .198

Blackman-Harris 0 .423 –0 .497 0 .079

�� Bergland, G.D., A G u ided Tour o f the Fast Fourie r T ransform ,IE E E S pectrum , Ju ly 1969, pp . 41–52.A genera l in troduction to FFT theory and app lica tions .

Brigham, E.O., The Fast Fourie r T ransform , P ren tice H a ll, Inc .,E ng lew ood C liffs , N .J ., 1974.T heory, app lica tions and im p lem enta tion o f FFT . Inc ludesd iscuss ion o f FFT a lgorithm s fo r N no t a pow er o f 2 .

Harris, F.J., O n the U se o f W indow s fo r H arm onic A na lys is w iththe D iscre te Fourie r T ransform , P roceed ings o f the IE E E , vo l. 66 ,N o. 1 , January 1978, pp . 51–83.C lass ic paper on w indow functions and the ir figures o f m erit, w ithm any exam ples o f w indow s.

Ramirez, R.W., The FFT Fundam enta ls and C oncepts , P renticeH all, Inc ., E ng lew ood C liffs , N .J ., 1985.P ractice orien ted, m any exam ples o f app lica tions.

# # #


��

B LA N K P A G E


� ��

��

In this Appendix, a general explanation of how the instrument’sstandard parameters are computed is followed by a table thatdefines and describes those parameters (page D–5).Proper determ ination of the top and base reference lines isfundam ental for ensuring correct param eter calculations. Theanalysis begins by com puting a histogram of the waveform data overthe tim e interval spanned by the left and right tim e cursors. Forexam ple, the histogram of a waveform transitioning in two states willcontain two peaks (F ig. D–1). The analysis w ill attem pt to identify thetwo clusters that contain the largest data density. Then the m ostprobable state (centroids) associated with these two clusters w ill becom puted to determ ine the top and base reference levels: the topline corresponds to the top and the base line to the bottom centroid.

Figure D–1

��

RIGHT CURSORLEFT CURSOR

rise fall

ampl pkpk

width

maximum

top

50 % (M esia l)

HIST

OG

RA

M*

minimumbase

*not

to s

cale

U ppe r T h resho ld(90 % A m p litude)

Low er T h resho ld(10 % A m p litude)


��

��

O nce top and base are es tim ated, ca lcu la tion o f the rise and fa lltim es is eas ily done (F ig .1 ). T he 90% and 10% thresho ld leve lsare au tom atica lly de term ined by the osc illoscope, us ing theam plitude (am pl) param eter.

T hresho ld leve ls fo r rise or fa ll tim e can a lso be se lec ted us ing

abso lu te o r re la tive se ttings (r@ level, f@ level). If abso lu te se ttings

are chosen, the rise or fa ll tim e is m easured as the tim e in te rva l

separa ting the tw o cross ing po in ts on a ris ing or fa lling edge. B utw hen re la tive se ttings are chosen, the vertica l in te rva l spannedbetw een the base and top lines is subd iv ided in to a percentile

sca le (base = 0% , top = 100% ) to de term ine the vertica l pos itionof the c ross ing po in ts .

T he tim e in te rva l separa ting the po in ts on the ris ing or fa llingedges is then es tim ated to yie ld the rise or fa ll tim e. T heseresu lts a re averaged over the num ber o f trans ition edges tha toccur w ith in the observa tion w indow .

Rising Edge Duration ( )∑=

−M r

i

ii T rT rM r

1

10901

Falling Edge Duration ( )∑=

−M f

i

ii T fT fM f

1

90101

W here M r is the num ber o f lead ing edges found , M f the num ber o f

tra iling edges found , x

iT r the tim e when rising edge i crosses the x%

level, andx

iT f the tim e when falling edge i crosses the x% level.

T im e param eter m easurem ents such as w id th , period , and de layare carried out w ith respect to the m es ia l re ference leve l (F ig .D –2), loca ted ha lfw ay (50% ) betw een the top and base re ferencelines .

T im e param eter es tim ation depends on the num ber o f cyc lesinc luded w ith in the observation w indow . If the num ber o f cyc les isnot an in teger, param eter m easurem ents such as rm s o r m eanw ill be b iased.

��


��

��

Figure D–2

T o avo id these b ias e ffec ts , the ins trum ent uses cyc licparam eters , inc lud ing crm s and cm ean, tha t res tric t theca lcu la tion to an in teger num ber o f cyc les .

T he osc illoscope enab les accura te d iffe ren tia l tim em easurem ents be tw een tw o traces — for exam ple , p ropagation ,se tup and ho ld de lays (F ig . D –3).

P aram eters such as Δc2d± requ ire the trans ition po la rity o f thec lock and da ta s igna ls to be spec ified .

RIGHT CURSORLEFT CURSOR

TWO FULL PERIODS: = 2cycles

first last

50 %

delay

PERIOD PERIOD

cmean, cmedian, crms, csdevcomputed on interval periods

width width width

freq period = 1/ duty width/period=

area, points, datacomputed between cursors

TRIGGERPOINT

(Mesial)


��

Figure D–3

M oreover, a hys teres is range m ay be spec ified to ignore anyspurious trans ition tha t does no t exceed the boundaries o f thehysteres is in te rva l. In F igure D –3, Δc2d− (1 , 2 ) m easures the tim ein terva l separa ting the ris ing edge o f the c lock (trigger) from thefirs t negative trans ition o f the da ta s igna l. S im ila rly, Δc2d+ (1 , 2 )m easures the tim e in te rva l be tw een the trigger and the nexttrans ition o f the da ta s igna l.

RIGHT CURSORLEFT CURSORTRIGGER POINT

DATA (1)

CLK (2)

THRESHOLD

C LO C K E D G E = P os itive Trans ition

D ATA E D G E = N egative Trans ition

HYST

ERES

IS

N o isy sp ikes igno red dueto H ysteres is band

Δ −c2d (1, 2)

Δc2d+(1, 2)


��

��

ampl A m plitude : M easures the d iffe rencebe tw een the upper and low er leve ls intw o-leve l s igna ls . D iffe rs from pkpk in tha tno ise , overshoo t, undershoo t, and ring ingdo N O T a ffec t m easurem ent.

top � base

(S ee F ig . D –1)

O n s igna ls N O T hav ing tw om a jo r leve ls (such as triang leor saw -too th w aves), re tu rnssam e va lue as pkpk .

area In teg ra l o f da ta : C om putes a rea o fw ave fo rm be tw een cu rso rs re la tive tozero leve l. V a lues g rea te r than ze rocon tribu te pos itive ly to the a rea ; va luesless than ze ro nega tive ly.

S um from firs t tolas t o f da ta

m u ltip lied byhorizon ta l tim ebe tw een po in ts(S ee F ig . D –2)

base Low er o f tw o m ost p robab le s ta tes(h igher is top ). M easures low er leve l intw o-leve l s igna ls . D iffe rs from m in in tha tno ise , overshoo t, undershoo t, and ring ingdo N O T a ffec t m easurem ent.

V a lue o f m ostp robab le low er

s ta te

(S ee F ig . D –1)

O n s igna ls N O T hav ing tw om a jo r leve ls (triang le o r saw -too th w aves, fo r exam p le ),re tu rns sam e va lue as m in .

cycles D ete rm ines the num ber o f cyc les o f aperiod ic w ave fo rm ly ing be tw een cu rso rs .The firs t cyc le beg ins a t the firs t trans itiona fte r the le ft cu rso r. The trans ition m ay bepos itive o r nega tive go ing .

N um ber o fcyc les o fpe riod ic

w ave fo rm(S ee F ig . D –2)

cmean C yclic m ean : C om putes the average o fw ave fo rm da ta . C on tra ry to m ean ,com putes the average over an in teg ra lnum ber o f cyc les , e lim ina ting b ias causedby frac tiona l in te rva ls .

A verage o f da tava lues o f an

in teg ra l num bero f pe riods

cmedian C yclic m ed ian : C om putes the average o fbase and top va lues over an in teg ra lnum ber o f cyc les , con tra ry to m edian ,e lim ina ting b ias caused by frac tiona lin te rva ls .

D a ta va lue fo rw h ich 50% o f

va lues a re aboveand 50% be low

crms C yclic roo t m ean square : C om putes thesquare roo t o f the sum o f squares o f da tava lues d iv ided by the num ber o f po in ts .C ontra ry to rm s , ca lcu la tion is pe rfo rm edover an in teg ra l num ber o f cyc les ,e lim ina ting b ias caused by frac tiona lin te rva ls .

1 2

1N

v i

i

N

( )

=∑

W here: v i denotes m easured

sam ple values, and N = num berof data points w ithin the periodsfound up to m axim um of 100periods.


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csdev C yclic s tandard devia tion : S tandarddevia tion o f da ta va lues from the m eanva lue over an in teg ra l num ber o f pe riods.C ontra ry to sdev, the ca lcu la tion isperfo rm ed over an in tegra l num ber o fcyc les , e lim ina ting b ias caused byfrac tiona l in te rva ls .

∑=

−N

i

i )m eanv(N

1

21 W here: v i denotes m easured

sam ple values, and N = num berof data points w ithin the periodsfound up to m axim um of 100periods.

data R etu rns the average o f a ll da ta po in ts . A ll da ta va lues inana lyzed reg ion

(S ee F ig . D –2)

Multi-value param eter especiallyvaluable for histogram s andtrends.

delay The tim e from trigger to trans ition :M easures the tim e be tw een trigger andfirs t 50% cross ing a fte r the le ft cu rso r. Itcan m easure p ropaga tion de lay be tw eentw o s igna ls by triggering on one andde te rm in ing de lay o f the o the r.

T im e be tw eentrigger and firs t50% cross ing

a fte r le ft cu rso r

(S ee F ig . D –2)

Δdly Δde lay: C om putes tim e be tw een the 50%

leve l o f tw o sources.

T im e be tw eenm idpo in t

trans ition o f tw osources

Δt@lv Δt a t leve l: C om putes the trans ition

be tw een se lec ted leve ls o r sources.

T im e be tw eentrans ition leve lso f tw o sources,

o r from trigger totrans ition leve l o fa s ing le source

R efe rence leve ls and edge-trans ition po la rity can bese lec ted . H yste res is a rgum entis used to d iscrim ina te leve lsfrom no ise in da ta .

Δc2d± Δclock to data ±: Com putes the difference in

tim e from the clock threshold crossing to

either the next (Δc2d+) or previous (Δc2d−)

data threshold crossing.

T im e from c lockth resho ld

cross ing to nexto r p revious edge

(S ee F ig . D –3)

Threshold levels of clock anddata signals, and edge-transitionpolarity can be selected.Hysteresis argum ent is used todifferentiate peaks from noise indata, w ith a good hysteresisvalue between half expectedpeak–to–peak value of signaland tw ice expected peak–to–peak value of noise.


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dur For s ing le sw eep w ave fo rm s, du r is 0 . Forsequence w ave fo rm s: tim e from firs t tolas t segm ent’s trigger. Fo r s ing lesegm ents o f sequence w ave fo rm s: tim efrom p revious segm ent’s to cu rren tsegm ent’s trigger. For w ave fo rm sproduced by a h is to ry function : tim e fromfirs t to las t accum u la ted w ave fo rm ’strigger.

T im e from firs t tolas t acqu is ition— fo r average ,

h is tog ram orsequence

w ave fo rm s

duty D uty cyc le : W id th as pe rcen tage o fpe riod .

w id th /period(S ee F ig . D –2)

f80–20% Fa ll 80–20% : D ura tion o f a pu lsew ave fo rm 's fa lling trans ition from 80% to20% , averaged fo r a ll fa lling trans itionsbe tw een the cu rso rs .

A verage dura tiono f fa lling80–20%trans ition

On signals NOT having two majorlevels (triangle or saw-toothwaves, for example), top andbase can default to maximumand minimum, giving, lesspredictable results, however.

f@level Fa ll a t leve l: D ura tion o f pu lse w ave fo rm 'sfa lling edges be tw een trans ition leve ls .

D ura tion o ffa lling edge

be tw eentrans ition leve ls

On signals NOT having two majorlevels (triangle or saw-toothwaves, for example), top andbase can default to maximumand minimum, giving, lesspredictable results, however.

Fa ll tim e : M easures the tim e be tw een tw ospec ified va lues on fa lling edges o f aw ave fo rm . Fa ll tim es fo r each edge a reaveraged to p roduce the fina l resu lt.

A rgum ents

Threshold Remote LowerLim it

UpperLim it

Default

Low er low 1% 45% 10%

U pper h igh 55% 99% 90%

fall

Threshold arguments specify two verticalvalues on each edge used to compute fall time.Formulas for upper and lower values:

low er va lue low er th resho ld= × +am p

base100

upper va lue upper th reshold= × +am p

base100

Tim e a t low erth resho ld �

Tim e a t upperth resho ld

averaged overeach fa lling edge

(S ee F ig . D –1)

O n s igna ls N O T hav ing tw om a jo r leve ls (triang le o r saw -too th w aves, fo r exam p le ), topand base can de fau lt tom ax im um and m in im um ,g iv ing , less p red ic tab leresu lts , how ever.


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first Ind ica tes the va lue o f the horizon ta l axisa t the le ft cu rso r.

H orizon ta l axisva lue a t le ft

cu rso r

(S ee F ig . D –2)

Indicates location of left cursor.Cursors are interchangeable: forexam ple, the left cursor m ay bem oved to the right of the rightcursor and first w ill give thelocation of the cursor form erlyon the right, now on the left.

freq Frequency: The period o f a cyc lic s igna lm easured as the tim e be tw een everyo ther pa ir o f 50% cross ings. S ta rting w iththe firs t trans ition a fte r the le ft cu rso r, theperiod is m easured fo r each trans itionpa ir. V a lues a re then averaged and therec ip roca l used to g ive frequency.

1 /period

(S ee F ig . D –2)

last Tim e from trigger to the las t (righ tm ost)cu rsor.

T im e from triggerto las t cu rso r

(S ee F ig . D –2)

Indicates location of the rightcursor. Cursors areinterchangeable: for example, theright cursor may be moved to theleft of the left cursor and first willgive the location of the cursorformerly on the left, now on theright.

maximum M easures the h ighest po in t in thew ave fo rm . U n like top , it does N O T assum etha t the w ave fo rm has tw o leve ls .

H ighest va lue inw ave fo rm

betw een cu rso rs

(S ee F ig . D –1)

G ives s im ila r resu lt w henapp lied to a tim e dom a inw ave fo rm , o r to a h is tog ram o fda ta o f the sam e w ave fo rm .B u t w ith h is tog ram s, the resu ltm ay inc lude con tribu tions fromm ore than one acqu is ition .C om putes horizon ta l ax isloca tion o f righ tm ost non-ze rob in o f h is tog ram ; no t to becon fused w ith m axp .

mean A verage o f da ta fo r a tim e dom a inw ave fo rm . C om puted as the cen tro id o fd is tribu tion fo r a h is tog ram . B u t w heninpu t is a pe riod ic tim e dom a in w ave fo rm ,it is com puted on an in teg ra l num ber o fpe riods.

A verage o f da ta

(S ee F ig . D –2)

G ives s im ila r resu lt w henapp lied to a tim e dom a inw ave fo rm o r h is tog ram o f da tao f the sam e w ave fo rm . B u tw ith h is tog ram s, the resu ltm ay inc lude con tribu tions fromm ore than one acqu is ition .


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median The average o f base and top va lues. A verage o f baseand top

(S ee F ig . D –2)

minimum M easures the low est po in t in a w ave fo rm .U n like base , it does N O T assum e thew ave fo rm has tw o leve ls .

Low est va lue ina w ave fo rm

betw een cu rso rs(S ee F ig . D –1)

G ives a s im ila r resu lt w henapp lied to a tim e dom a inw ave fo rm o r h is tog ram o f da tao f the sam e w ave fo rm . B u tw ith h is tog ram s, the resu ltm ay inc lude con tribu tions fromm ore than one acqu is ition .

over− O vershoo t nega tive : The am ount o fovershoo t fo llow ing a fa lling edge ,expressed as a pe rcen tage o f am p litude .

base m in im um

am pl

−×

� �

100

(S ee F ig . D –2)

The w ave fo rm m ust con ta in a tleast one fa lling edge . O ns igna ls N O T hav ing tw o m a jo rleve ls (triang le o r saw -too thw aves, fo r exam p le ), it m ayN O T g ive p red ic tab le resu lts .

over+ O vershoo t pos itive : The am ount o fovershoo t fo llow ing a ris ing edge ,expressed as a pe rcen tage o f am p litude .

m axim um top

am pl

−×

� �100

(S ee F ig . D –1)

W avefo rm m ust con ta in a tleast one ris ing edge . O ns igna ls N O T hav ing tw o m a jo rleve ls (triang le o r saw -too thw aves, fo r exam p le ), it m ayN O T g ive p red ic tab le resu lts .

period The period o f a cyc lic s igna l m easured asthe tim e be tw een every o ther pa ir o f 50%cross ings. S ta rting w ith the firs t trans itiona fte r the le ft cu rso r, the period ism easured fo r each trans ition pa ir, w ithva lues averaged to g ive a fina l resu lt.

( )∑=

−M r

i

ii T rT rM r

1

50501

(S ee F ig . D –2)

W here : M r is the num ber o f

lead ing edges found , M f the

num ber o f tra iling edges

found , x

iT r the tim e when rising

edge i crosses the x% level,

andx

iT f the tim e when falling

edge i crosses the x% level.

pkpk P eak-to -peak: The d iffe rence be tw eenthe h ighest and low est po in ts in aw ave fo rm . U n like am p l, it does no tassum e the w ave fo rm has tw o leve ls .

m axim um �m inim um

(S ee F ig . D –1)

Gives a similar result when appliedto a time domain waveform orhistogram of data of the samewaveform. But with histograms, theresult may include contributionsfrom more than one acquisition.

phase The phase difference between the signalanalyzed and the signal used as reference.

Phase differencebetween signaland reference

points The num ber of points in the waveformbetween the cursors.

Num ber of pointsbetween cursors(S ee F ig . D –2)


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r20–80% R ise 20% to 80% : The dura tion o f thepu lse w ave fo rm ’s ris ing trans ition from20% to 80% , averaged fo r a ll ris ingtrans itions be tw een the cu rso rs .

Average durationof rising 20–80 %

transition


r@level R ise a t leve l: The dura tion o f a pu lsew ave fo rm 's ris ing edges be tw eentrans ition leve ls .

Duration of risingedges betweentransition levels


Rise time: Measures the time between twospecified values on a waveform’s rising edge(10–90%). Rise times for each edge areaveraged to give a final result.

Arguments

Threshold Rem oteLowerLim it

UpperLim it

Default

Lower low 1% 45% 10%

Upper high 55% 99% 90%

r ise

Threshold arguments specify two vertical valueson each edge used to compute rise time.

Formulas for upper and lower values:

low er va lue low er th resho ld= × +am p

base100

upper va lue upper th reshold= × +am p

base100

Time at upperthreshold � Time at

lower thresholdaveraged over each

rising edge

(S ee F ig . D –1)



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rms R oot M ean S quare o f da ta be tw een thecurso rs — abou t the sam e as sdev fo r azero -m ean wave fo rm .

1 2

1N

v i

i

N

( )

=∑

(S ee F ig . D –2)

Where: vi denotes measured sample

values, and N = number of datapoints within the periods found up toa maximum of 100 periods. Gives asimilar result when applied to a timedomain waveform or histogram ofdata of the same waveform. But withhistograms, the result may includecontributions from more than oneacquisition.

sdev S tandard devia tion o f the da ta be tw eenthe cu rso rs — abou t the sam e as rm s fo ra ze ro -m ean w ave fo rm .

∑=

−N

i

i )m eanv(N

1

21

(S ee F ig . D –2)

Where: vi denotes measured

sample values, and N = number ofdata points within the periods foundup to maximum of 100 periods.Gives a similar result when applied toa time domain waveform or to ahistogram of data of the samewaveform. But with histograms, theresult may include contributions frommore than one acquisition.

t@level Tim e a t leve l: The tim e from trigger (t=0 )to cross ing a t a spec ified leve l.

T im e from triggerto c ross ing leve l

top Higher of two most probable states, the lowerbeing base. This is characteristic of rectangularwaveforms and represents the higher mostprobable state determined from the statisticaldistribution of data point values in the waveform.

V a lue o f m ostp robab le h igher

s ta te

(S ee F ig . D –1)

G ives s im ila r resu lt w henapp lied to tim e dom a inw ave fo rm o r h is tog ram o f da tao f sam e w ave fo rm . B u t w ithh is tog ram s, resu lt m ay inc ludecon tribu tions from m ore thanone acqu is ition .

width The width of a cyclic signal determined byexamining 50% crossings in the data input. Ifthe first transmission after the left cursor is arising edge, the waveform is considered toconsist of positive pulses, and width the timebetween adjacent rising and falling edges.Conversely, if it is a falling edge, pulses areconsidered negative, and width the timebetween adjacent falling and rising edges. Forboth cases, widths of all waveform pulses areaveraged for a final result.

W id th o f firs tpos itive o r

nega tive pu lseaveraged fo r a lls im ila r pu lses

(S ee F igs. 1 , 2 )

S im ila r to fw hm , w h ich app lieson ly to h is tog ram s, how ever.

# # #


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BLANK PAG E


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The ASCII waveform storage feature allows waveforms to besaved to a mass-memory device in any of three ASCIIformats: Spreadsheet, MathCad, and MATLAB. Each formatis tailored for a commonly used analysis package. The user-interface changes that support ASCII waveform storage arefound in the STORE menu (see Chapter 13).T he tab le be low sum m arizes the bas ic layout o f the th reeform ats . E xam ples o f the use o f each fo rm at a re g iven on thefo llow ing pages. Your PC screen indicates the m odel nam e andserial num ber of the instrum ent being used.

Format HeaderForm at

inc ludes som eform of

header beforethe data

TimeValues

Form at s torestim e va luesw ith eacham plitude

va lue

AmplitudeValues

Form at s toresam plitude

va lues

SequenceTimesHeadercontains

sequence timeinformation for

each sequencesegment

Multi-Segment

Form atconcatenates

m ultip lesegm ents o f a

sequencew aveform

Dual ArrayForm at a llow s

dua l-arraydata (i.e .

E x trem a, orcom plex FFT)to be s tored

Spreadsheet Yes Yes Yes Yes Yes Yes

MathCad Yes Yes Yes Yes Yes Yes

MATLAB N o N o Yes N o Yes N o

�� Once stored in ASCII, waveforms cannot be recalledinto the DSO.


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This example was created using Microsoft Excel for Windows.A waveform stored in Spreadsheet format may be read intoMicrosoft Excel using the File -> Open window:

Excel w ill now ask for m ore inform ation about the file type. Ensurethat the ‘Delim ited’ option is selected in the first step of the W izard.


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The next step allows the specific delim iter to be specified. TheSpreadsheet form at generated by the instrum ent uses a com m a (,)to delim it colum ns. Ensure that this is selected.


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T he th ird and fina l s tep a llow s the fo rm at o f the co lum ns to bespec ified . T he ‘genera l’ fo rm at fo r each co lum n shou ld be used(th is is the de fau lt).


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After you click the Finish button, a display sim ilar to that followingshould appear.


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�� Plotting the data from a waveform requires the use of a scatter plotbased on the data in the first two colum ns, w ith the first colum n usedas the X values (from Row 6 in this exam ple).


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The header created for the Spreadsheet form at contains all theinform ation required to extract various elem ents of a sequencewaveform . The following form ulas m ay be used to extractinform ation such as the start and end row of the data for a givensegm ent, or the trigger tim e of a given segm ent.

Segm entStartRow := (DesiredSegm ent * D2) + B2 + 5

Segm entEndRow := Segm entStartRow + D2 -1

TrigTim e= INDIRECT(ADDRESS(DesiredSegm ent +3;2;4))

T im eS inceF irs tT rig= IN D IR E C T (A D D R E S S (D es iredS egm ent+3;3 ;4 ))

P lotting the data from all segm ents using a scatter plot w ill result inall segm ents overlaid (sim ilar to the oscilloscope’s display ofsequence traces in persistence m ode).

��


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These examples were created using MathSoft’s MathCad forWindows. On this page, the procedure for reading andgraphing a file for a single segment is shown. The example onpage E–10 is for multiple segments.

�� This single-segm ent exam ple is valid for MathCad Versions 3.1 to 7:


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�� The following M athCad exam ple dem onstrates how to extract datafrom a given segm ent. The data used for this exam ple consisted oftwo segm ents of three sam ples each, allowing the entire im portedm atrix to be shown.


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This exam ple was created using M athW orks’ M ATLAB Version4.2c.1 for W indows.

Reading and graphing a waveform in M ATLAB m ay be achievedwith two sim ple com m ands, as the following exam ple shows. Thefirst com m and loads the file into a m atrix which is autom aticallynam ed after the file. The second com m and plots this m atrix.


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�� Format

�� Fields in bold type are constants that are present inthe output file, as shown. Fields in italic are variables thatare filled in when the file is written.

<scope id> , <scopeseria l>Segments, <num seg>, SegmentSize,

<num pts>Segment, TrigTime,

TimeSinceFirstSegment#1, < trig tim e(1)> , 0.0... ...#<num seg>, < trig tim e(num seg)> ,

< trigde lta (num seg)>Time, Ampl, [Ampl1]x(0), y (0), [y1(0)]x (1), y (1), [y2(0)]... ...x (num gseg*num pts), y (num seg*num pts),[y1(num seg*num pts)]

Single-Segment ExampleLECROYLC584AL,LC58412345Segments,1,SegmentSize,502Segment,Trig Time,TimeSinceFirstSegment#1,21 Mar 1990 9:37:08,0.0Time,Ampl0.0,10.1,2...


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Multi-Segment ExampleLECROYLC584AL,LC58412345Segments,3,SegmentSize,502Segment,Trig Time,TimeSinceFirstSegment#1,21 Mar 1990 9:37:08,0.0#2,21 Mar 1990 9:37:13,5.0#3,21 Mar 1990 9:37:15,7.0Time,Ampl0.0,10.1,2...0.0,1.10.0,2.1...0.0,1.050.0,2.05

Dual-Array ExampleLECROYLC584AL,LC58412345Segments,1,SegmentSize,502Segment,Trig Time,TimeSinceFirstSegment#1,21 Mar 1990 9:37:08,0.0Time,Ampl0.0,1.1,1.10.1,2.1,2.1...

��

� The basic structure of the Spreadsheet format is aheader containing scope identification information,followed by a block containing trigger times for multi-segment waveforms, followed by the data itself.

� This format is compatible with the ASCII import of theLeCroy LW4xx Arbitrary Function Generator.


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�� Format<“scope id”><“T riggerT im e”><num seg> <num pts>Segment TimeSinceFirstSegment1 0.0... ...<num seg> <trigde lta (num seg )>Time Ampl Ampl1<x(0)> <y(0)> [<y1(0)> ]<x(1)> <y(1)> [<y1(1)> ]... ...<x(num gseg*num pts)> <y(num seg*num pts)>

[<y1(num seg*num pts)> ]

Single-Segment Example“LECROYLC584AL,LC58412345”“23-March-90,12:44:23”1 502Segment TimeSinceFirstSegment1 0.0Time Ampl0.0 10.1 2.....


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Multi-Segment Example“LECROYLC584AL,LC58412345”“23-March-90,12:44:23”3 502Segment TimeSinceFirstSegment1 0.02 5.03 7.0Time Ampl0.0 10.1 2.....0.0 1.10.1 2.1.....0.0 1.050.1 2.05

��

� The format created for MathCad is very similar to theSpreadsheet format, but with some differences due to theway MathCad interprets the header information.

� One of the most important of these is that the absolutetrigger time is only given for the first segment, with relativetimes (in units of seconds) included for each segment.

� Another difference is that the scope identification and triggertime are wrapped in quotes to ensure that MathCad does notattempt to import them.


��

�� Formaty(0)y(1)...y (num seg*num pts)

Single-Segm ent Exam ple1.01.11.2...4.5

# # #

��

� The MATLAB format is simple, without header information and havingamplitude values only.

� Multiple segments will be appended without a separator.� Only one value from the pair of amplitude values present in a dual-array

will be stored.


��

�

AC, 3-2, 8-5, C-15Acquisition Memory, C-4

increas ing it by com b in ingchanne ls , 2 -1 , 7 -5

Acquisition Modes, 6-1, 7-6, A-4Acquisition Summary, 5-3, 6-3,

16-1Acquisition Summary field, 4-9Adapter, 1-3ADC (Analog–to–Digital

Converter), 2-1, 7-1, 7-2, 7-5Add new Directory, 12-15Advanced Color Management,

2-3, 11-1, 11-2Aliasing, C-5, C-17Altitude, A-11Amplitude, 12-23, 14-7, D-5

in FFT, 10-19Analog

S ing le S w eep, 11-17ANALOG PERSIST, 4-2, 11-13,

11-14

Analog Persistence™, 2-3, 11-1,

11-5, 11-15, 11-19, A-8Area, D-5Arithmetic Setup, 10-9as, 8-39ASCII, 13-1, 13-2, 13-3, E-1ASCII Form ats, A-11, E-1, E-2,

E-3, E-4, E-7, E-8, E-9, E-10,E-11, E-12, E-13, E-14, E-15,E-16

Audible feedback, 12-21AUTO, 6-2, 7-11A u to S c ro ll , 10-8AUTO SCROLL menus, 10-8AUTO SETUP, 4-2, 4-7, A-7Autocalibration, 2-2, 12-19, A-11Auto-Combine Mode, 7-7Automatic, 7-7Automatic Recalibration, 12-19autoprint, 12-3Autosetup, A-7

Auto-Store, 12-9, 13-2Average, A-9Average Setup, 10-10Averaging, B-3

�

Background, 11-2, 11-21, 12-2BACKSPACE, 12-16, 12-17Bandwidth, A-1Bandwidth Lim iter, A-3Bandwidth Lim iting (BW L), 5-3,

5-6Base, D-1, D-2, D-5Battery, 12-10, A-11Baud Rate, 12-6Bi-level. See W indow Pattern

TriggerBinary, 13-1, 13-2Block diagram

LC 334/374 /534 /574 S eries ,2 -4

LC 564/584 S eries, 2 -5BMP, 12-2, 12-8Boolean AND, 8-21

�

CablingP rin te r, 12 -5

CAL BNC Setup, 12-1, 12-23CAL/BNC, 14-15Calibration, 2-2, 5-5, 12-19, 12-23,

A-11Capture information, 4-9Capture Time, 10-18CAUTION, 3-1Centroids, D-1Centronics, 12-2, 12-3Change, 11-22CHANGE COLORS, 11-20CHANGE PARAM, 14-11, 14-12CHANGE PARAMETERS, 14-10Channels, A-1CHANNELS, 4-2character, 12-16, 12-17


��

Chassis Term inal, 3-2Circuit Failures

tes ting fo r us ing E xc lus ionTrigger, 8 -11

Cleaning and Maintenance, 3-3CLEAR INACTIVE menu, 16-5CLEAR SW EEPS, 4-6, 10-3,

10-4, 10-14, 11-14, 14-8, 14-9,14-10

Clock Accuracy, A-5Clock Edge, 14-14, D-4cm/division, 12-3Coherent Gain, C-17Color

C hang ing C o lo rs , 11 -20 ,11-21 , 11 -22

C opying C o lo r S chem es,11-22

Color Association, 11-1, 11-2Color Control, 11-20Color Graded Persistence, 11-1,

11-15, 11-17, 11-19, A-8Color Links, 11-1, 11-3Color Management, 11-1, 11-2,

11-4Color Palettes, 11-1, 11-20,

11-21, 11-22Color Saturation, 11-17, 11-19Color Scheme menu, 11-20Color Schemes, 11-1color to, 11-22Colors, 11-4Combining Channels, 2-1, 7-5,

7-6, 7-7, 8-4, 10-5Conform ity, 1-3, 3-1, A-12Continuous Averaging, 10-3,

10-10Controls

M enu bu ttons and knobs,4 -2

COPY FILES, 12-18Copy from , 11-22COPY SCHEME, 11-22COPY TEMPLATE TO, 12-14

COPY TEMPLATE TO FLPY,12-13

Copying Color Schemes, 11-22Copying files between storage

media, 12-10Coupling, 5-3, 8-5, 8-36, 8-38,

8-43, 8-45, A-5COUPLING button, 5-2Cursors

A bso lu te , 14 -1 , 14 -2 , 14 -5 ,A -10

A m plitude , 14 -1co lo r, 11 -21D iffe rence , 14 -5in FFT (Fast Fourie r

Transfo rm ), C -12P ers is tence , 14 -1R efe rence , 14 -5R e la tive , 14 -1 , 14 -2 , 14 -5 ,

A -10T im e, 14-1

Cursors Measure, 12-19CURSORS/MEASURE, 4-5, 14-5Custom Menus 14-5Custom Parameters, 14-6, 14-10,

14-11, 14-12, 14-13, 14-14Cycles, D-5

in pa ram ete r m easurem ents ,D -2

Cyclic Mean, D-5Cyclic Median, D-5Cyclic Param eters, D-3Cyclic Root Mean Square, D-5Cyclic Standard Deviation, D-6

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Data, D-6Data density, D-1Data Edge, 14-14Data Format, 13-3Data Maps, 11-1, 11-15, 12-12Data Points, 11-21Day/Mnth/Year, 12-4DC, 8-5, C-15


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DC Accuracy, A-3DC Level, 12-23DC Offset

com pensa ting fo r, 10 -15Deadtime

reduc ing it us ing S equenceM ode, 7 -3

Decim ationin FFT, 10-20

Delay, D-6DELAY, 6-3Delay By, 10-16DELETE THIS DIRECTORY,

12-15Deleting Files, 12-9Deskew function, 10-16Differential Time Measurements,

D-3Digital Filters, 10-11Digitizers, A-1Directory, 12-7, 12-11, 12-15,

12-16, 12-17Disk Density, 12-13Display, 2-3, 11-1, 11-2, 11-4,

11-5, 11-8, 11-9, 11-10, 11-11,11-12, A-8on-screen sections and

fie lds , 4 -9S tandard , 11 -7XY, 11 -7

DISPLAY, 4-5, 11-13, 11-16,11-18

Display Area Size, A-8DISPLAY button, 11-7Display Order, 11-3Display Resolution, A-8Display Scaling, 10-20Display Setup, 11-13

genera l, 11 -7XY, 11-16

DISPLAY SETUP, 11-1, 11-14,11-18

Displayed Trace Label, 4-9, 10-3,10-20

DistortionFFT, C -4

DO COPY, 12-18

DO RECALL, 13-4, 13-5, 14-21,15-3

DO STORE, 13-2DOS. See UTILITIES:Mass

StorageDot Join, A-8Dropout Trigger, 8-28, 8-42, A-6Dual Grid, 11-9Duration, D-7Duty, D-7Dynam ic Range

im proving it, C -6

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Earth, 3-2, 3-3ECL/TTL, 5-3Edge menu, 8-45Edge Trigger, 8-1, 8-2, 8-5, 8-8,

8-34Edge Trigger with Hold-off, 8-5Edge Trigger with Hold-off by

Events, 8-7Edge-Qualified Trigger, 8-20,

8-26, 8-41Edge-Qualified Trigger with W ait,

8-23ENBW , C-17Enhanced Resolution Filtering,

10-11, B-1, B-2, B-3, B-4, B-5,B-6, C-6

Enhanced Resolution Setup,10-11

ENTER NEW FILE NAME, 12-16Envelope, 10-12ERES, A-9Errors

de tecting them in rem otecon tro l. S ee R em oteC ontro l A ss is tan t

Events, 8-7, 8-21, 8-23, 8-34Trigger H o ld -o ff by, 8 -7

Excel, E-2Exclusion Trigger, 8-12, 8-36Expansion Factor, 12-3EXT, 8-4, A-6


��

External Clock, 7-8, 7-9, A-5External Reference, A-5Extrema, 10-3, 10-12, 11-3, A-9

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Fall, D-2Fall 80–20 % , D-7Fall at Level, D-7Fall time, 14-9, D-2, D-7Falling edge, 14-13FFT (Fast Fourier Transform),

10-18, 10-19, A-9, C-1, C-8,C-9, C-17

FFT Algorithms, C-14FFT Average Setup, 10-14FFT Error Messages, C-13FFT Interruption, 10-13FFT menus, 10-13, 10-14FFT result menu, C-10, C-11FFT Span, 10-18, 10-19, 10-20,

10-21, 10-22FFT W indows, 10-13, C-5, C-6,

C-11, C-17, C-19, C-20Fields, 8-39File, 13-5, 14-21File Deleting, 12-9File Nam ing, 12-8, 12-9, 12-15,

12-16File Transfers, 12-10File Type, 12-16Files, 12-7, 12-9, 12-10, 12-12,

12-14, 12-18, 15-3Fill, 12-9Filters, B-1, B-2, C-3, C-4, C-18FIR (Finite Impulse-Response)

filter, B-1, B-2, C-6Firmware Update, 12-19First, D-8FLASH UPDATE, 12-22Floor, 10-12

in extrem a w ave fo rm s, 10 -3Floppy Disk, 12-7, 12-9, 12-10,

12-11, 12-12, 12-13, 12-15,

13-1, 13-2, 13-5, 14-21, 15-1,15-2, A-11

FLPY UTIL, 12-12for Math use max points menu,

10-19, C-9format, 12-2Format, 12-3FORMAT FLPY, 12-13Format Hard Disk, 12-14Frequency, 11-7, 12-1, 12-23,

B-2, C-1, C-3, C-4, C-5, C-9,C-12, C-15, C-20, D-8

Frequency bins, C-18Frequency Range, C-18Frequency Resolution, 10-18,

C-2, C-8, C-11, C-19Frequency Span, 10-19, 10-20,

C-8from, 15-3from Card, Flyp or HDD, 15-2from Memory, 13-4Front Panel, 12-19Front Scope Cover, 1-3Front-panel Controls, 4-2Full Dialog. See Remote Control

AssistantFULL FORMAT, 12-14Full Screen, 2-3, 8-14, 11-1, 11-10FULL SCREEN, 4-2, 11-10Fuses, 1-3, 3-3

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General Instrument Reset, 4-7G litch Trigger, 8-10, 8-35, 8-36G lobal BW L, 12-19. See

Bandwidth Lim iting. SeeBandwidth Lim iting

GPIB, 4-6GPIB Address, 12-6GPIB and RS232, 12-1, 12-2,

12-3, 12-20, A-11GPIB Port, 12-5, A-11GPIB/RS232 Setup, 12-1, 12-6Graticules, A-8


��

Grid Color, 11-21Grid intensity, 11-13Grids, 11-7, 11-8, 11-9, 11-11,

11-13, 11-14, 11-16, 11-18, A-8Ground, 3-2, 3-3Ground and Trace Level markers,

4-9

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Hard Disk, 12-7, 12-10, 12-14,12-15, 13-1, 13-2, 13-5, 14-21,15-1, 15-2

Hardcopy, 2-3E xpans ion fac to r, 12 -3

Hardcopy Setup, 12-1, 12-2, 12-3Harm onics, C-2, C-5HDD (portable hard disk), 12-7,

12-14, 12-15, 13-2, 13-5,14-21, 15-1, 15-2

HFin Triggering, 8 -5

H igh-Frequency Triggering, 8-5Histograms, A-9, D-1Holdoff, 8-43Hold-off, 8-5, 8-19, 8-34, A-6Hour/Min/Sec, 12-4HPGL, 12-2Humidity, 3-1Hysteresis, 14-13, 14-14, D-4hysteresis menu, 14-13, 14-14

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In, 12-19Input Coupling, A-3Input Impedance, 5-3, A-3INSERT, 12-16, 12-17Interfacing, 2-3, A-11Interleaving, 7-2Internal Memory, 13-1, 13-4, 13-5,

15-1Internal Printer Setup, 12-3Interpolator Resolution, A-5Interval Trigger, 8-12, 8-13, 8-14,

8-15, 8-16, 8-38

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Landscape, 12-3Last, D-8Leading Edge, D-2Leakage, C-5, C-11, C-19Level, 14-13LEVEL, 6-4, 8-1level menu, 14-13LINE, 8-4LOAD CHANGES NOW , 12-4Lobes, C-2, C-5, C-17, C-19Log, 12-20Low-Frequency Triggering, 8-5Low-pass Filtering, B-2, B-4, C-6

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Magnitude, C-4, C-6, C-10, C-15,C-16

Maintenance, 1-2MAKE THIS DIRECTORY, 12-17Mask Testing, 14-15, 14-19,

14-20, 14-21Mass Storage, 12-7, 12-15, 12-16,

12-18MASS STORAGE, 12-10, 12-12,

12-14Math Functions, 9-1, 10-2, 10-6,

10-15, 10-18, 10-19, 10-20S peed ing them up , 10 -5

MATH SETUP, 9-2Math Type, 10-16Math Type menu, C-11Mathcad, E-1, E-9, E-10, E-14,

E-15MathCad, 13-3MATLAB, 13-3, E-1, E-11, E-16Maxim a

in extrem a w ave fo rm s, 10 -3Maxim um , D-8Maxim um Input, A-4Maximum Sampling Rate, 7-2, 7-5Mean, D-8MEASURE, 14-16Measure Gate, 11-21


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Measurement Gate Highlighting,11-4, 11-21

Median, D-9Medium -to-H igh-Frequency

Triggering, 8-5Memories, 2-1, 13-1, 13-4, 13-5,

15-1, 15-2, A-10Mem ory, A-2, A-3, A-9, C-4, C-12Memory Card, 12-7, 12-10, 12-15,

13-1, 13-2, 13-5, 14-21, 15-1,15-2

Memory Used/AvailableSum m ary, 16-5

Menu buttons and knobs, 4-2, 4-3Menu Options, 4-4Menu-Entry buttons, 4-3, 4-5, 4-6,

5-3, 9-2, 11-7, 11-10, 12-1,13-1, 13-4, 14-5

Menusm oving th rough them , 4 -3 ,

4 -5Mesial, D-2Message Field, 4-9Microprocessor, A-9Minim a

in extrem a w ave fo rm s, 10 -3Minimum, D-9mode, 12-23MORE DISPLAY, 11-20More Display Setup, 11-13, 11-14,

11-16, 11-18MORE VERSION

INFORMATION, 16-2Multiple Grids, 11-12Multi-Zoom, 10-8MULTI-ZOOM & AUTO-SCROLL,

10-6

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Neutral Color, 11-21use in M easurem ent G a te

H igh ligh ting , 11 -4NEW DIRECTORY, 12-17New Directory on Card, 12-17

Noise Reduction, 10-3, B-2, B-6NORM, 6-2, 7-11, 10-3Number of points, 7-6, C-14, C-19Nyquist Frequency, 10-19, 10-20,

B-2, C-4, C-5, C-9, C-12, C-19

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Objectsd isp laying them , 11 -1 , 11 -2

Octal Grid, 11-12Offset behavior, 5-3, 7-11, 12-1,

12-19OFFSET knob, 5-1Offset Range, A-1Offset scaling, 4-7Opaque Mode, 11-3, 11-20Operand, 10-9Operating Environment, 3-1, A-11Operator, 10-9Options installed

in fo rm ation on , 16 -2OR interval, 8-38Output Formats, A-11output to, 12-3Over +, D-9Over�, D-9

Overflow, B-3Overlap Management, 11-1, 11-3,

11-20Overlays Color, 11-21Overload, 3-3, 5-3, 5-6Oversampling, B-1Overvoltage, 3-1

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Packing and Shipment, 1-3page feed, 12-2PANEL SETUPS, 4-6, 15-1, 15-2,

15-3PANEL SETUPS button, 15-1Param eter Analysis, A-9Parameter Categories, 14-11,

14-12


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Param eter Display, 11-10Parameter symbols, 14-6, 14-7Parameters, 10-3, 14-6, 14-8,

14-9, 14-10, 14-11, 14-12,14-13, 14-14, 14-15, 14-16,14-17, 14-18, 14-19, 14-20,14-22, A-10, D-1, D-5, D-6,D-7, D-8, D-9, D-10, D-11

Parity, 12-6Pass/Fail Testing, 11-4, 12-23,

14-6, 14-15, 14-16, 14-17,14-18, 14-19, 14-20, 14-21

Pattern, 8-22Pattern Trigger, 8-17, 8-18, 8-19,

8-37, 8-43, A-6PC, 12-7, A-11PCMCIA. See UTILITIES:Memory

CardPeak Detect, 7-2, 7-6, A-4Peak–to–Peak, 14-8, D-9pen number, 12-2Period, D-9Periodic Signals, C-6Persist, 11-15Persist for, 11-15, 11-19Persistance Decay, 11-5Persistence, 11-13, 11-14, 11-16,

11-18, 11-19, 14-1, A-8PERSISTENCE, 11-15Persistence data maps, 11-5,

11-14m em ory a lloca tion , 16 -5

Persistence Setup, 11-14, 11-15Phase, C-10, D-9Phase Response, B-2Picket Fence Effect, C-4, C-20plot size, 12-2Plotters, 12-2, A-11Points, D-9Pollution Degree, 3-1, A-12Portrait, 12-3POSITION, 9-2, 10-6Post-Trigger, 6-3, A-5Power, 3-3, A-11Power Average, C-16Power Averaging, 10-14Power Density, 10-13, C-10, C-16

Power Density Spectrum, C-4,C-20

Power OnS e lf-Tes t, 3 -3

Power Requirements 3-2Power Spectrum, 10-13, C-4,

C-10, C-16, C-20Power-off, 3-1Power-on, 3-1Precise Tim ing Measurements,

10-1Pre-Trigger, 6-3, A-5Primary menus, 4-3printer, 12-2Printers, 12-2, 12-3, 12-5, A-11Probe Attenuation, 5-3Probe Calibration, 5-5Probes, 1-3, 5-5, A-7ProBus, 1-3, 5-5Processors, 2-1Protective Conductor Term inal,

3-2Pulse W idth, 8-13, 8-35, 8-36,

8-37, 8-46Pushbutton auto-repeat, 12-21

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Quad Grid, 11-9, 11-10Qualifications

in Triggering , 8 -2Qualified First Trigger, 8-24, 8-25,

8-44Qualified Triggers, 8-20, 8-21,

8-40, 8-41, 8-44, A-7Qualifier. See Qualified TriggersQUICK FORMAT, 12-14

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RAM, A-4, A-5, A-9Read time cursor amplitudes,

12-19Real Time Clock field, 4-9Real, Real + Imaginary, Imaginary

FFT, C -10


��

Real-Time DisplayS ee R o ll M ode , 7 -3

RECALL W ’FORM, 4-5, 13-4,13-5

Recall/Save, 15-1Recalling Setups, 15-2, 15-3Record, 7-8Record Length

m axim is ing it, C -8Record up to, 7-7, 7-8Reducing Noise, 10-3, B-2, B-6Reference Memories, 10-5Relative Mode. See

Cursors:RelativeRelative Time Cursors, 10-1Remote Control, 2-3Remote Control Assistant, 12-19,

12-20Remote Enable, 4-4Resam ple

deskew m ath function , 10 -16Rescale Setup, 10-17RESET, 9-2, 10-1Resolution, B-1, B-2, B-3Resolution Bandwidth

in FFT, 10-18RESTORE DEFAULT NAME,

12-16Return, 1-3RETURN, 4-3, 11-10RIS (Random Interleaved

Sampling), 2-2, 7-1, 7-2, 7-6,7-7, 8-28, A-4A U TO , 6 -2S N G L, 6 -3S TO P , 6 -1

Rise, D-2Rise 20–80 % , D-10Rise at Level, D-10Rise time, 14-9, D-2, D-10Rising edge, 14-13Roll Mode, 7-1, 7-3

A U TO , 6 -2N O R M , 6 -2S N G L, 6 -3

S TO P , 6 -1Roof, 10-12

in extrem a w ave fo rm s, 10 -3Root Mean Square (rms), 14-8,

D-2, D-11RS232 Cabling, 12-3RS-232-C, 4-6RS-232-C Connector Pin

Assignments, 12-5RS-232-C Port, 12-5, A-11Runt Trigger, 8-30, 8-31, 8-45,

A-7

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Safety, 3-1, A-12Sam ple C lock, 7-6, 7-8, 7-10Sam ple rate

increas ing it by com b in ingchanne ls , 2 -1 , 7 -5

Sam ple Rate, A-2, A-3, A-4Sampling, 7-8, 7-9

FFT, C -1S a m p l in g M o d e s , 7-1Sam pling Period

in FFT, 10-19Sampling Rate, 7-3, 7-6, B-1Sampling thresholds, 7-8Saturate at, 11-17, 11-19Saturation, 11-6, 11-14, 11-15Saving Setups, 15-1Scale Factors, A-3Scaling

in FFT, 10-20Scallop Loss, C-4, C-17, C-20Scope Explorer, 2-3SCREEN DUMP, 4-6, 12-2Screen Intensity

G rid , 11 -13 , 11 -16 , 11 -18W ave fo rm and Text, 11 -13 ,

11-16 , 11 -18Screen Save, 11-20Screen Type, A-8Secondary menus, 4-3


��

Segments, 6-1, 6-2, 7-3, 7-8, 7-9,7-10, 10-3, E-8, E-10

SELECT ABCD, 9-1SELECT CHANNEL, 5-1Self-Test, 3-3Sensitivity, A-1Sequence, 7-10Sequence Mode, 7-3, 7-7, 7-8,

7-9, 10-3, 10-6, 12-19, A-4A U TO , 6 -2N O R M , 6 -2S TO P , 6 -1

Serial number, 16-2Service and Repair, 1-2SET CLOCK, 12-4SET TO, 12-23Setup ASCII Format, 13-2SETUP parameter menus, 14-13Setup Recall, 2-3Setups, 2-3Shape, 12-23SHOW STATUS, 16-1SHOW STATUS button, 4-6Signal Interval, A-6Signal W idth, A-6Signal–to–noise(SNR) ratio

im proving it us ing E nhancedR eso lu tion F ilte ring , B -1 ,B -2

SINGLE, 7-11Single-Shot Acquisition, 10-3, A-4S in g le - S h o t A q u is i t io n , 7-1Single-Shot Mode, 6-2, 7-6, 7-7Size, A-11Slew Rate Trigger, 8-32, 8-33,

8-46, A-7slope, 8-34Slope, 8-46, 14-13, A-5SMART Trigger, 2-2, 8-1, 8-2,

8-10, 8-11, 8-12, 8-13, 8-14,8-15, 8-16, 8-17, 8-18, 8-19,8-20, 8-21, 8-23, 8-26, 8-28,8-30, 8-31, 8-32, 8-33, 8-35,8-36, 8-37, 8-38, 8-39, 8-40,8-41, 8-42, 8-43, 8-44, 8-45,8-46, A-6

SMARTMem ory, A-4

SNGL, 6-2Software version information, 16-2Source Trace, 10-7Sources, A-5Special Modes, 7-11, 12-1, 12-19Spectral Analysis, 10-18, B-2,

C-1, C-2Spectral Power Averaging, C-6,

C-7Spreadsheet, 13-3, E-1, E-2, E-3,

E-4, E-7, E-8, E-12, E-13Standard Deviation, 14-8, D-11Standard Display, 11-7, 11-13,

11-14Standard Param eters, D-1Standard Time Parameters, 14-9Standard Voltage Parameters,

14-8Standby, 11-20State-Qualified Trigger, 8-20, 8-40State-Qualified Trigger with W ait,

8-21Statistics, 14-6, 14-8, 14-9, 14-10STOP, 6-1, 7-11, 10-3Stop bits, 12-6Storage

C opy F iles , 12 -18Storage Availability, 12-9store, 13-2STORE, 13-1STORE W ’FORMS, 13-1, 13-2Sum m ary, 16-1Summed Averaging, 10-3, 10-10SYSTEM SETUP, 4-5System Sum m ary, 16-2

�

Temperature, 3-1, A-11Template, 12-10, 12-13, 12-14TEMPLATE AND FORMATTING,

12-12Text & Tim es Sum m ary, 16-3Text Color, 11-2, 11-21Threshold, 8-30, 8-32, 8-33, 8-45TIFF, 12-2, 12-8


��

Time, 8-21, 8-23in d isp lay, 11 -7Trigger H o ld -o ff by, 8 -34

Time and Frequency field, 4-9Time at Level, D-11Time intervals, D-2Time Parameter measurements,

D-2Time Resolution

im proving it w ith Zoom , 10-1TIME/DATE, 12-4Time/Date Setup, 12-1TIME/DIV, 6-3Time/Div Range, A-5Timebase, 14-19, 16-1TIMEBASE, 6-1, 10-19, 10-21TIMEBASE + TRIGGER, 4-2Timebase Clock, 7-1TIMEBASE EXTERNAL, 7-8, 7-9Timebase scaling, 4-7TIMEBASE SETUP, 6-4, 7-6Timebase summary, 16-1Timebase System, A-5Timeout, 8-22, 8-28, 8-42Tim ing Parameters, 14-13to, 13-4, 13-5to be set to, 12-16to Card, Flyp or HDD, 15-1tolerance, 14-20Top, D-1, D-2, D-11Trace and Ground Level markers,

4-9Trace Color, 11-21Trace Display, 11-15TRACE ON/OFF, 9-1, 11-3,

11-21Traces

selection of, 5 -1Tracking, 14-8, 14-9, 14-10Trailing Edge, D-2Transient signals, C-1, C-11Transparent Mode, 11-1, 11-3,

11-20TRIGGER, 6-1Trigger Amplitude, 8-4

Trigger Comparator, A-6Trigger Configuration field, 4-9Trigger Controls, 8-1Trigger Coupling, 8-4, 8-34, 8-36,

8-38, 8-45, 8-46Trigger Delay, 4-9, 6-3, 7-1, 8-28,

8-41, 8-44, 14-9Trigger Events, 8-8, 8-34, 8-40Trigger Holdoff, 8-43Trigger Hold-off, 8-5, 8-34Trigger Level, 6-4, 8-1, 8-4, 8-8,

8-17, 8-43, 14-13Trigger Level arrows, 4-9Trigger Level scaling, 4-7Trigger Modes, 6-1trigger on, 8-39Trigger Out, 12-23Trigger Range, 8-4, A-6Trigger Ready, 12-23TRIGGER SETUP, 6-4, 8-1, 8-34,

8-35Trigger S lope, 8-5, 8-42Trigger Source, 6-4, 8-3, 8-4,

8-34, 8-38, 8-42, 8-45, 8-46Trigger Status field, 4-9Trigger summary, 16-1Trigger System, 2-2, A-5Trigger Threshold, 8-17, 8-18,

8-19, 8-40, 8-41, 8-44Trigger Tim ing, A-6Trigger window, 8-13, 8-38Triggering, 7-5, 8-1, 8-2, 8-9,

8-34, 10-3A U TO , 8 -1N O R M , 8 -1S TO P , 8 -1

TV signal on, 8-39TV Trigger, 8-26, 8-39, A-7TV Type, 8-39

�

use Math?, 10-16Using, 11-15, 11-17, 11-19UTILITIES, 4-5, 7-11, 12-1


��

F ile Transfe rs , 12 -10F loppy D isk , 12 -7 , 12 -12 ,

12-13G P IB port, 12 -5H ard D isk , 12 -7 , 12 -14H ardcopy S e tup , 12 -2 , 12 -3M ass S to rage , 12 -1 , 12 -7 ,

12-10M em ory C ard , 12 -7P rin te rs , 12 -2 , 12 -3R S -232-C port, 12 -5S pec ia l M odes, 12 -1 , 12 -19

�

V/div O ffset, 5-3, 5-6Validation

in triggering , 8 -20VAR button, 5-2Vertical Offset, 5-1Vertical Resolution, A-3

increas ing it, B -5Vertical Sensitivity, 5-1VGA, A-11VOLTS/DIV knob, 5-2Volts/div scaling, 4-7

�

W ait, 8-44W arnings, 3-2W arnings Color, 11-21W arranty, 1-1, A-12W aveform and Text intensity,

11-13W aveform Mathematics, 10-2,

10-5, 10-6W aveform Processing, 10-5, A-9,

C-1, C-7, C-11, C-12, C-14,C-17, C-18

W aveform Recall, 13-4, 13-5W AVEFORM RECALL, 4-5W aveform Status, 16-4W aveform Store, 13-1, 13-3W eight, A-12W hich files, 12-18

W idth, 8-36, 8-37, 8-46, D-11W indow Pattern Trigger, 8-19W indow Trigger, 8-8with, 8-45, 8-46with window menu, C-5work with, 12-15W rap, 7-7, 7-8, 7-10, 7-11, 12-9

�

XY Display, 11-7, 11-11XY Dual Display, 11-11XY Persist Setup, 11-18XY Persistence, 11-18XY SETUP, 11-17, 11-19

�

ZERO, 6-3Zoom, 9-1, 9-2, 10-1, A-8ZOOM, 9-2, 10-6Zoom menu, 10-7Zoom of Math Functions, 10-1

# # #

LC X X X -O M -E R ev K IS S U E D : D ecem ber 1999

��

Argentina: Search SA

54-11-4775-8544

Australia: Philips Test and Measurem ent

2 9888 8222

Austria: Dewetron Gm bH

0316 3070

Benelux: LeCroy Ltd.

1 235 524 288

Brazil: ATP/Hi-Tek Electronica Ltda

11 725 5822

Canada: Allan Crawford Assoc. Ltd.

M ississauga: 905 890 2010N. Vancouver: 604 878 1002

Chile: Sistem as de Instrum entacion Ltda

2 6951137

Denmark: Lutronic ApS

43 42 9764

Eastern Europe: Elsinco Gm bH, Vienna

1 815 04 00

Finland: O rbis OY, 0478 830

France: LeCroy Sarl,

1 69 18 83 20

Germany: LeCroy Europe Gm bH,

6221 82700

Greece: IFIPCO, 1 67 25 970

Hong Kong: Schm idt Electronics

852 250 70333

Israel: Am m o, 3 547 2747

Italy: LeCroy S.r.l., Venice

41 456 9700

Japan: LeCroy Japan Corp.

Osaka: 6 396 0961Tokyo: 3 3376 9400Tsukuba: 298 41 5810

Korea: LeCroy Korea Ltd.

2 3452 0400

Mexico: Electroingenieria de Precision SA

559 7677

New Zealand: Philips Test and Measurement

649 8494 160

Norway: Avantec AS

22 76 38 70

Pakistan: Electro Tech Corp. Ltd.

21 493 9593/5171

Portugal: M .T. Brandao Lda.

2 830 27 09

Singapore: Abex Eng. Ltd.

841 2818

South Africa: W estplex Ltd.

11 787 0473

Spain: MT Brandao SL

1 803 1767

Sweden: MSS AB

8 544 107 00

Switzerland: LeCroy SA

North: 62 885 8050W est: 22 719 2228

Taiwan: Lecoln Tech. Co.

2 232 6368

Thailand: Measuretronix Ltd.

2 375 2733

Turkey: NETES

212 237 32 26

Unite Arab Emirates: A rab E ng ineers fo r

T rad ing C o. L td 899 0220/0440

United Kingdom, Ireland: LeCroy Ltd.

1 235 524 288

United States: 1 800–5–LeCroy

(autom atically connects you to your localsales office)

Vietnam: Schm idt Vietnam Co Ltd.

4 8346 186

Documents

User Manual Oscilloscope Lecroy Lc534L