New product applications: Thermoelectric DIP relay features cost, size, and performance advantages

Thermoelectric DIP relay features cost, size, and performance advantages

This D I P re lay, w h i c h f e a t u r e s a ther-moe lec t r lca l ly cont ro l led ac tua tor that re ­p l a c e s the induct ion coil of convent iona l re lays , opera tes o n e i ther a c or d c cur­rent , is ra ted at 5 a m p e r e s , a n d has built-in t i m e - d e l a y capabi l i ty . In th e latching conf igurat ion , it r e m a i n s a c t u a t e d e v e n af ter the current h a s b e e n shut off.

B e c a u s e the coi l less d e v i c e is not s u b j e c t to the h igh-vo l tage sp ikes inher­ent in coil re lays , it is suited for uses such a s low- level IC control that require low noise genera t ion . Its t i m e - d e l a y and la tching- logic capabi l i t ies m a k e it useful in au tomot ive and a p p l i a n c e appl icat ions .

T h e actuator , a b imeta l l ic strip that is c o a t e d with an e lec t r i ca l insulator and an e lec t r ica l ly resist ive m a t e r i a l , hea ts up w h e n a n e lectr ic cur ren t is app l ied . Two a c t u a t o r s , bending in opposi te d i rect ions, a r e used in e a c h re lay . W h e n the current

is app l ied , the m e c h a n i s m snaps into its a l te rna te conf igurat ion to o p e n or c lose a circuit . Nei ther cur rents be low the d e ­sired level nor m o m e n t a r y p o w e r surges will t r igger the dev ice .

D e s i r e d t ime de lays of a minute or m o r e c a n be incorpora ted into the re lay des ign , e l iminat ing the n e e d for a s e p a ­rate t ime -de lay circuit . Actuat ion de lay and r e l e a s e de lay c a n be independent ly contro l led , with two or m o r e f ixed de lays coupled to the s a m e contac t . R e l e a s e t ime is nominal ly o n e half the ac tua t ion t ime , with repeatabi l i ty of ± 5 p e r c e n t a t a g iven a m b i e n t t e m p e r a t u r e .

R e s p o n s e t i m e c a n b e e i ther an a d v a n ­tage or a d i s a d v a n t a g e . T h e usual r e ­sponse t i m e of the re lay is 9 0 to 6 0 0 m s , wh ich is slower than t h e ac tua t ion t i m e of convent iona l re lays; h o w e v e r , the s lower response t ime m e a n s the relay is less

suscept ib le to a c c i d e n t a l t r igger ing f rom transient v o l t a g e s , p o w e r surges , or inter­ruptions of t h e cont ro l vo l tage .

Other f e a t u r e s that m a k e the coi l less relay sui table for a w ide range of c o m ­merc ia l a p p l i c a t i o n s inc lude its low cost , small s ize , l o w noise genera t ion , nonin-duct ive n a t u r e , a n d availabil i ty of t i m e delays a n d logic funct ions.

The re lay wi l l p e r f o r m to speci f icat ion , including d e l a y - t i m e a c c u r a c y , ove r 0 to + 1 2 0 ° C a n d will w i thstand pro longed ambient e x p o s u r e to + 1 4 0 ° C a n d 9 5 -percent r e l a t i v e humidi ty .

The re lay is ava i lab le in s i n g l e - p o l e / double - throw a n d d o u b l e - p o l e / d o u b l e -throw m o d e l s . Load vol tage is 1 to 2 8 volts dc a n d 1 to 1 1 0 volts a c . Life ex ­pectancy is f i ve mil l ion c y c l e s m i n i m u m at 1 - a m p e r e res is t ive load .

For fur ther in format ion , c o n t a c t O A K Switch D iv . , C rys ta l L a k e , I I I . 6 0 0 1 4 .

Circle No. 40 on Reader Service Card

T w o a c t u a t o r s , b e n d i n g in opposite d i rec t ions , a r e use*d in e a c h relay. T h e b imeta l l i c str ips ( A ) m o v e the c o n t a c t s ( B ) w h e n cur rent is appl ied .

.Insulator

Low-cost, 8-bit monolithic multiplying D/A converter features 85-ns settling

This series of 8-bit monol i th ic mult ip ly­ing D / A conver te rs of fers a n 8 5 - n s set ­tl ing t ime , c o m p l e m e n t a r y / d i f f e r e n t i a l , h i g h - c o m p l i a n c e cur rent outputs , a n d un i ­versa l logic inputs. M a t c h i n g b e t w e e n fu l l -sca le and r e f e r e n c e cur ren ts to within 1 LSB e l iminates ca l ibrat ion in most a p ­pl icat ions. M o n o t o n i c mult ip ly ing perfor ­m a n c e is a t ta ined over a w i d e re fe r ­e n c e - i n p u t - c u r r e n t r a n g e .

D i rec t in ter fac ing with C M O S , T T L , D T L , ECL , and H T L is provided by a n o p ­t ional logic threshold a d j u s t m e n t , and the logic inputs a c c e p t a swing of - 1 0 to 4 - 1 8 volts. A c c o r d i n g to the m a n u f a c t u r ­e r , the ser ies is the first D / A conver ter to in te r face direct ly wi th the N M O S a n d

P M O S outputs of t h e m a n y a v a i l a b l e microprocessor R A M s .

Us ing the noninver ted or " t r u e " output results in posi t ive- t rue binary c o d i n g ; using the c o m p l e m e n t a r y output results in negat ive - t rue binary c o d i n g . Both outputs m a y be used s imul taneous ly in a var ie ty of d i f ferent ia l -output conf igurat ions , such as the genera t ion of of fset binary c o d i n g , driving c e n t e r - t a p p e d coi ls , and in- l ine driving. Resist ive output te rmina t ion e l i m ­inates output opera t iona l ampl i f iers in m a n y appl icat ions. T h e r e f e r e n c e inputs a c c e p t a posit ive or negat ive dc re fe r ­e n c e , a fast pulse input, or an a c mu l t i ­plying signal to beyond a 1 - M H z b a n d ­width.

All m o d e l s h a v e g u a r a n t e e d perfor­m a n c e over t h e ± 4 . 5 - to ± 1 8 - v o l t p o w e r supply r a n g e , wi th 3 3 - m W p o w e r c o n ­sumption a t t a i n a b l e at ± 5 - v o l t suppl ies . The c o m p a c t s ize and low p o w e r c o n ­sumption m a k e the ser ies useful in por ta ­ble a n d m i l i t a r y / a e r o s p a c e appl icat ions . Dev ices p r o c e s s e d to M I L - S T D 8 8 3 a r e avai lable .

Pr ices in quant i t ies of 1 0 0 r a n g e f r o m $ 6 . 5 0 e a c h for the 0 8 C Z ( ± 0 . 3 9 p e r c e n t m a x i m u m nonl inear i ty f r o m 0 to 7 0 ° C ) to $ 2 0 e a c h for the 0 8 A Z ( ± 0 . 1 pe rcen t m a x i m u m nonl inear i ty f rom — 5 5 to + 1 2 5 ° C ) .

Addi t ional in format ion is ava i lab le f r o m Precision M o n o l i t h i c s , Inc . , 1 5 0 0 S p a c e Park Dr . , S a n t a C l a r a , Calif . 9 5 0 5 0 .

Circle No. 41 on Reader Service Card

8 0 I E E E spectrum S E P T E M B E R 1975

Isolation amp combines ±2500-volt common-mode rating and 150-dB rejection Sensor ·ν ^ . Γ

Shield Power common

+15-volt power

«bl5*voft common power supply

High output

Low output

T h e m o d e l 2 7 5 isolat ion ampl i f ie r prov ides a combina t ion of ± 2 5 0 0 volts of c o m m o n -m o d e vo l tage , 1 5 0 dB of c o m m o n - m o d e r e j e c t i o n , and nonl inear i ty of ± 0 . 0 5 p e r c e n t .

T h e mode l 2 7 5 industr ial isolation a m ­p l i f i e r—wi th a ± 2 5 0 0 - v o l t c o m m o n - m o d e vo l tage c a p a b i l i t y — a l l o w s smal l -s ignal var iat ions to be m e a s u r e d o n h igh-vol tage power l ines. T h e isolator 's 1 5 0 - d B c o m ­m o n - m o d e re jec t ion rat io assures the a c ­c u r a c y of t h e s e m e a s u r e m e n t s . U n d e r the e x t r e m e condi t ions of a 1-k$2 source i m b a l a n c e and a f r e q u e n c y of 6 0 Hz , the c o m m o n - m o d e - r e j e c t i o n ratio is still 1 2 0 dB m i n i m u m a n d is typical ly 2 0 0 0 0 0 0 to 1. For every 1 0 0 volts of c o m m o n - m o d e

Unl ike most w a v e f o r m genera tor m o d ­ules or ICs ava i lab le , the distort ion of this w a v e f o r m genera tor r e m a i n s low over an e x t r e m e s w e e p or p r o g r a m m i n g r a n g e , a c c o r d i n g to the m a n u f a c t u r e r . The user p r o g r a m s the f r e q u e n c y with a resistor.

T h e m o d u l e has t h r e e independent ly buf fered outputs for sine w a v e , t r iangle w a v e , and s q u a r e w a v e . It c a n be oper ­a ted f r o m a single 15-vol t supply and d r a w s less than 3 0 m A . T h e s q u a r e - w a v e output is TTL, M O S , and C M O S c o m p a t ­ible . T h e m o d u l e e m p l o y s t w o ICs: a t r i -

vo l tage that is appl ied to the dif ferential inputs of the m o d e l 2 7 5 , only 1 0 0 μ\ί will a p p e a r as the di f ferent ia l input.

T h e isolator is avai lab le in three ver ­sions d e p e n d i n g on the requi red t e m p e r a ­ture p e r f o r m a n c e : mode ls 2 7 5 J , K, and L h a v e input of fset vo l tage drifts of ± 2 5 , ± 1 5 , and ± 5 μ \ / / ° 0 m a x i m u m , r e s p e c ­tively.

Nonl inear i ty , a source of error that cannot be r e d u c e d by ex terna l ad just ­m e n t , is also he ld to a low leve l . T h e user

ang le - and s q u a r e - w a v e genera tor , and a sine conver te r . Opera t ing t e m p e r a t u r e r a n g e is - 2 5 to + 7 5 ° C .

T h e f requency -se t t ing f e a t u r e permi ts the user to fix or* vary the f r e q u e n c y be­t w e e n 4 5 H z a n d 4 5 k H z with a single re ­sistor. Adding a capac i tor ex tends the f r e q u e n c y r a n g e to over e ight d e c a d e s , f r o m 0 . 0 0 1 H z to 2 0 0 k H z . No t r imming of any kind is n e c e s s a r y .

T h e output f r e q u e n c y has a guaran teed t e m p e r a t u r e stabil ity of 1 0 0 p p m / ° C m a x ­i m u m and a supply vol tage d e p e n d e n c e

m a y select this p a r a m e t e r b a s e d on per ­f o r m a n c e r e q u i r e m e n t s . M o d e l s J , K, a n d L offer ± 0 . 1 5 , ± 0 . 1 , and ± 0 . 0 5 percent m a x i m u m nonl inear i ty , respect ive ly .

T h e ga in of the m o d e l 2 7 5 m a y be var ­ied b e t w e e n 1 a n d 1 0 0 by ad just ing a s in­gle resistor, w h i c h results in a full ± 1 0 - v o l t i n p u t / o u t p u t capabi l i ty . T h e iso­lator requi res only a single 1 2 - to 18-volt dc supply and d r a w s only 15 m A in the qu iescent s ta te .

The isolater h a s b e e n des igned to w i th ­stand e n v i r o n m e n t s of high humidity, shock , v ibra t ion , t e m p e r a t u r e cycl ing, mois ture , p r e s s u r e , a n d other condit ions stated in M I L - S T D - 2 0 2 E . It wi thstands a line vo l tage of 1 1 5 volts a c direct ly across the di f ferent ial input.

The signal output c a n be f loated at up to 2 0 0 volts with respec t to the power supply c o m m o n . B e c a u s e it is a th ree -port isolator with its input isolated f rom the power supply a n d the output isolated f rom both the input a n d the supply, the model 2 7 5 provides m a x i m u m protect ion .

The isolator is speci f ied for operat ion f r o m 0 to 7 0 ° C . It is p a c k a g e d in a n 8 9 . 7 -by 6 4 . 3 - by 2 2 . 6 - m m ( 3 . 5 - by 2 .5 - by 0 .88 - in ) m o d u l e a n d is pr iced at $ 7 9 , $ 9 0 , and $ 1 0 0 for the m o d e l s J , K, a n d L. D e ­livery is f r o m s tock .

For addit ional in format ion , contac t A n ­alog D e v i c e s , I n c . , P .O. Box 2 8 0 , Route 1 Industrial Park , N o r w o o d , M a s s . 0 2 0 6 2 .

Circle No. 42 on Reader Service Card

i m u m resistor -control va lue , the ability to use polar ized c a p a c i t o r s direct ly , a min i ­m u m output pu lse width of 2 7 ns, input loading of 0 .6 unit load , and an output drive of 1 2 . 5 unit load.

T h e d e v i c e is ava i lab le f r o m stock. Pr ice of a 9 2 S 0 2 in a plastic D I P is $ 1 . 5 6 in quant i t ies of 100 to 9 9 9 .

D a t a shee ts a r e ava i lab le f r o m the D i g ­ital Products D iv . , Fairchi ld C a m e r a and Instrument Corp. , 4 6 4 Ellis St. , Mountain V iew, Calif. 9 4 0 4 2 .

Circle No. 43 on Reader Service Card

of less than 0.1 p e r c e n t / v o l t . A s w e e p and F M input a l lows a c h a n g e

in f r e q u e n c y of g r e a t e r than 1000 :1 with a l inearity of 0 .2 pe rcen t . Throughout this r a n g e , the s y m m e t r y and l inearity of all w a v e f o r m s r e m a i n s h igh .

T h e m o d u l e is housed in a 3 .75 - by 3 . 7 5 - by 1 . 0 - c m ( 1 . 5 - by 1.5- by 0 .4- in) epoxy p a c k a g e with gold-p la ted pins on 2 0 0 - m i l c e n t e r s .

Pr ice is $ 3 9 in singie quant i t ies. T h e modu le is ava i l ab le f r o m stock.

Con tac t In te rdes ign , Inc. , 1 2 5 5 R e a m -wood A v e . , Sunnyva le , Calif. 9 4 0 8 6 .

Circle No. 44 on Reader Service Card

Propagation delay of 12 ns from a high-performance, dual monostable multivibrator

T h e 9 6 S 0 2 , a h i g h - p e r f o r m a n c e , dual m o n o s t a b l e mul t iv ibrator , uses an a d ­v a n c e d Schot tky p r o c e s s to improve speed and stability and to reduce re ­qui red t i m i n g - c a p a c i t o r s ize .

Pulse width is va r iab le over a range of 1 3 0 0 to 1 by m e a n s of a n externa l res is ­tor contro l . T h e d e v i c e fea tures pulse width var iat ion of less than ± 0 . 2 p e r c e n t over speci f ied t e m p e r a t u r e and vo l tage r a n g e s , and h a s a p ropagat ion de lay of

12 ns. It is re t r iggerab le and rese t tab le , and

o p e r a t e s up to a 1 0 0 - p e r c e n t duty cyc le . Both posit ive a n d negat ive tr igger inputs a re provided, a n d a Schmit t tr igger on the positive input r e d u c e s noise sensitivity.

Accord ing to the m a n u f a c t u r e r , the 9 6 S 0 2 is part icular ly suitable for long d e ­lays or a l a rge resistor-control led delay range . Other f e a t u r e s include: 0 . 1 - M F c a ­paci tor requi red for 1 0 0 ms de lay at m a x -

Waveform generator module offers sine-wave distortion of only 0.3 percent maximum

N e w nroduct amplications 81

new product applications Miniature, precision film res! of 10 ohms to 100 megohms

T h e s e 1 0 - o h m to 100-MS2 precis ion re ­sistors are o f fe red in C K 0 6 p a c k a g e s that m e a s u r e only 1.94 c m s q u a r e (0 .3 in square ) and 0 . 2 5 4 c m (0 .1 in) thick. The radial leads h a v e a s tandard spacing of 0 . 5 0 8 c m ( 0 . 2 in) for handl ing by auto­mat ic insertion e q u i p m e n t .

D e v e l o p e d to m e e t the n e e d for high-stabil i ty, precis ion resistors for use in high-i m p e d a n c e c i rcu i ts , t h e s e M K resistors offer the fol lowing fea tures : • S tandard res is tance t o l e r a n c e of ± 1 p e r c e n t , and t o l e r a n c e s as c lose as 0.1 p e r c e n t on spec ia l order . • A power rat ing of 0 . 7 5 watts at ± 1 2 5 ° C , with dera t ing for operat ing at t e m p e r a t u r e s a s high a s + 1 7 5 ° C . • A range of opera t ing t e m p e r a t u r e s of - 5 5 to + 1 7 5 ° C . © T e m p e r a t u r e coef f ic ients of 50 p p m / ° C for va lues up to 10 M12 and 8 0

stors come in CK06 cases

p p m / ° C f rom 10 to 1 0 0 Μ12 ( f rom - 1 5 to + 1 0 5 ° C r e f e r e n c e d to + 2 5 ° C ) . • Extended-l i fe stabil i ty that is typical ly bet ter than 0.05 p e r c e n t per 1 0 0 hours, β M a x i m u m w o r k i n g vo l tage of 4 0 0 volts.

W h e n used in resist ive divider ne t ­w o r k s , all va lues of these M K resistors t r a c k to within 4 0 p p m / ° C . W h e n r e ­qu i red , special m a t c h e d sets of these r e ­sistors c a n be spec i f i ed for T C t rack ing to within 5 p p m / ° C .

The resistors a r e const ruc ted of h igh-stability M ic ronox res is tance f i lms f i red onto a solid c e r a m i c substrate . The res is ­tor is then e n c a p s u l a t e d inside a t ransfer -m o l d e d case . L e a d w i res a r e c o n ­structed of t inned 2 2 g a u g e c o p p e r .

Pr ices on the " e x t e n d e d r a n g e " M K r e ­sistors a re approx imate ly $ 2 e a c h in 1000-uni t quant i t ies . Del ivery is four to six w e e k s .

Small size, low price, and 1-MS conversion are features of 8-bit A / D converter

T h e low-cost M N 5 1 0 0 is o n e half the size of c o m p e t i t o r s ' 8-bit A / D conver te rs , and a c h i e v e s 1 - M S convers ion s p e e d s .

T h e model M N 5 1 0 0 8-bit A / D conver t ­er, housed in a 2 4 - p i n , h e r m e t i c D I P p a c k a g e , prov ides a typica l convers ion t i m e of 1 μ ε and 1.5 ps wors t c a s e , whi le

mainta in ing ± Y 2 - L S B l ineari ty over t h e full operat ing r a n g e of 0 to + 7 0 ° C . T h e mode l M N 5 1 0 0 H g u a r a n t e e s this per for ­m a n c e over the r a n g e of - 5 5 to + 8 5 ° C .

These units m e a s u r e 3 . 3 0 by 2 .03 by 0 . 3 6 c m (1 .3 by 0 . 8 by 0 .14 in) e a c h a n d a r e pr iced at $ 1 9 5 in single units for t h e M N 5 1 0 0 and $ 2 9 5 for the M N 5 1 0 0 H .

The conver te rs g u a r a n t e e ze ro error of ± V 2 LSB at 2 5 ° C a n d ± 1 LSB at 7 0 ° C , a n d ful l -scale e r ro r of ± 1 LSB at 2 5 ° C a n d ± 2 LSB at 7 0 ° C . N o t e m p e r a t u r e coeff ic ients a r e spec i f i ed , b e c a u s e t h e full ef fect of any swi tch e r rors or t e m p e r ­a tu re ef fects a r e incorpora ted in t h e wors t -case spec i f ica t ions .

The conver te rs a c h i e v e faster c o n v e r ­sion t imes if l ess resolut ion is requ i red ,

T h e C K 0 6 c a s e in wh ich this 100-MS2 resistor is p a c k a g e d h a s res is tance v a l u e s in s t a n d a r d ± 1 -percent and nons tandard ± 0 . 1 - p e r c e n t t o l e r a n c e s .

S t a n d a r d M K resistors in the r a n g e of 10 o h m s to 5 Μ12 a re pr iced at about 5 0 cen ts e a c h in 1000-un i t quant i t ies. Proto­type quant i t ies a re ava i lab le in t w o to th ree w e e k s .

Contac t C a d d o c k Electronics , I n c . , 3 1 2 7 C h i c a g o Ave . , Rivers ide, Cal i f . 9 2 5 0 7 .

Circle No. 45 on Reader Service Card

a n d c a n b e easi ly t runcated to 5- , 6 - , or 7-bit o p e r a t i o n .

E a c h conver te r opera tes f r o m ± 1 5 - v o l t and + 5 - v o l t supplies and dissipates 1 1 2 5 m W ( typica l ) and 1 5 5 0 m W (worst c a s e ) .

T h e a n a l o g input ranges ava i lab le to the user inc lude six unipolar r a n g e s ( - 2 0 , - 1 0 , - 5 , ± 5 , + 1 0 , a n d ± 2 0 volts) a n d t h r e e bipolar ranges ( ± 2 . 5 , ± 5 , a n d ± 1 0 vol ts ) .

A c c o r d i n g to the manufac t u r e r , t h e M N 5 1 0 0 o c c u p i e s half the board a r e a and o n e sixth the v o l u m e of a c o m p e t i ­tor's 8-bit A / D converter .

De l ivery of either the M N 5 1 0 0 or t h e M N 5 1 0 0 H is two to four w e e k s . Addi t ion­al in format ion is avai lab le f r o m M i c r o N e t w o r k s C o r p . , 3 2 4 Clark St . , W o r c e s ­ter, M a s s . 0 1 6 0 6 .

Circle No. 46 on Reader Service Card

T h e s e thermis to r f lakes f ind app l ica t ion in a var ie ty of detect ion a n d control u s e s . B e c a u s e of the f lakes very s m a l l s i ze , t h e r m a l a n d infrared t i m e cons tan ts a r e r e d u c e d , a n d sensitivity is i m p r o v e d .

Thermistor flakes, 0.5 by 0.5 mm, range in value from 25 kilohms through 1 megohm

A c c o r d i n g to the m a n u f a c t u r e r , this fami ly of "thinistor" f l a k e s (smal l thermis ­tor chips) inc ludes the smal les t chips ava i l ab le in the industry. B e c a u s e of the f l a k e s ' smal l s ize , t h e r m a l and infrared t i m e constants a r e r e d u c e d , and infrared sensitivity is improved . Typica l t ime c o n ­stants now ava i lab le a re 2 0 m s , and typi­ca l infrared t i m e constants a r e 1 6 0 ms .

T h e new f l a k e s c a n b e u s e d at higher chopp ing f r e q u e n c i e s as a result of the lower t ime constant .

T h e f lakes c a n be used in IR p y r o m e ­ters for the contro l of a u t o m a t i c assembly opera t ions a n d industrial p rocesses . As

part of IR cont inuous p r o c e s s ana lyze rs , the f lakes are u s e d in the analysis of g a s ­e o u s and liquid f lows and the control of f u r n a c e t e m p e r a t u r e s .

The f lakes a l s o find appl ica t ion in f i re control , pass ive IR intrusion a l a r m s , o v e r - t e m p e r a t u r e sensors , t h e r m a l d e t e c ­tors, and b i o m e d i c a l m e a s u r e m e n t s . In IR detectors , t h e f l akes c a n be used to eva luate the integrity of spo t -we lded joints a n d to m e a s u r e laser power .

Contact V i c t o r y Eng ineer ing C o r p . , Victory Rd . , Spr ingf ie ld , N .J . 0 7 0 8 1 .

Circle No. 47 on Reader Service Card

82 I E E E spectrum S E P T E M B E R 1975

Display connector permits variation of card slot length, width, and contact placement

T h e ES ser ies of display c o n n e c t o r s , wh ich is c o m p a t i b l e wi th both gas -d is ­c h a r g e and l iquid-crystal d isplays, a l lows designers to speci fy any n u m b e r of c o n ­tac ts , any c o n t a c t locat ion , a n d any body length and width a c c o m m o d a t i o n without specia l tooling c h a r g e s .

The series is ava i l ab le with both 0 . 2 5 4 - c m or 0 .1 - in ( E S 1 ) and 0 . 1 2 7 - c m or 0 .05 - in ( E S 5 ) c o n t a c t spac ing . In basic f o r m , it is a s ing le -s ide , s i n g l e - r e a d ­out, e d g e b o a r d style. Us ing this c o n ­cept , designers c a n speci fy a w ide range of substrate l e n g t h s — b e g i n n i n g with a m i n i m u m of 2 . 5 4 c m (1 in) and cont inu­ing up to a m a x i m u m of 1 5 . 2 4 c m (6 in) in 0 . 1 2 7 - c m ( 0 . 0 5 - i n ) i n c r e m e n t s . T h e ES ser ies c a n a c c o m m o d a t e nomina l sub-substrate th icknesses of % 4 , Vie. and 1 / 8 in.

The series e m p l o y s a dua l -de f lec t ion contact design to c o m b i n e o p t i m u m indi­vidual contact p ressure with m i n i m u m in­

sert ion force . D e s i g n e r s have the opt ion of using any n u m b e r of c o n t a c t s f r o m 1 0 through 6 0 on the E S 1 , and 2 0 through 1 2 0 on the E S 5 . Contac t locat ion o n p l a c e m e n t , with relat ion to the length of the card slot, is a lso opt ional .

Both mode ls f e a t u r e posit ive subst ra te " index regist rat ion." This is a c c o m p l i s h e d by m e a n s of a posit ioning spring that c a n b e located on ei ther the right or left e n d of the connector . This , c o m b i n e d with t h e des igner 's c h o i c e of con tac t locat ion , provides opt ional subst ra te or ienta t ion , if n e e d e d for registrat ion purposes .

T h e ES ser ies also a c c o m m o d a t e s c e ­r a m i c substrates as wel l as c i rcui t c a r d s requir ing s ing le - readout c o n n e c t o r s .

For c o m p l e t e in format ion , c o n t a c t D a l e E lectronics , Inc . , East H i g h w a y 5 0 , Y a n k ­t o n , S . D a k . 5 7 0 7 8 .

Circle No. 48 on Reader Service Card

T h e ES s e r i e s of g a s - d i s c h a r g e and l i ­qu id-crysta l c o n n e c t o r s permi ts a des ign ­er to speci fy any n u m b e r of con tac ts , any contact l o c a t i o n , a n d any body length and width a c c o m m o d a t i o n wi thout spec ia l tooling c h a r g e s .

Schottky TTL bus transceivers offer 15-ns driver and receiver propagation delays

T h i o rvair r»f Qohr>HLrw T T I n n a H h u e

t ransceivers , the A m 2 6 S 1 0 and A m 2 6 S 1 1 , provide 1 5 - n s driver and re ­ce iver propagat ion d e l a y s . Both products fea ture open-co l l ec to r dr ivers with 1 0 0 - m A current -s ink ing capabi l i ty , wh ich permi ts te rminat ion of 5 0 - o h m t r a n s m i s ­sion lines. T h e s e t r a n s c e i v e r s a re d e ­signed for s i n g l e - e n d e d , t w o - w a y c o m m u ­nicat ions in bus -or ien ted d ig i ta l -process­ing systems.

The circuit pair o p e r a t e s f rom a single

C\_v/r»lt ci irvnlw F a r h h a c a nniA/<ar_Hn\A/n w .w.. · • • • ~ r-f ea tu re that l imits bus loading to 100 μ Α a n d is fully c o m p a t i b l e with s tandard Schot tky TTL sys tems. The bus dr ivers h a v e a c o m m o n e n a b l e for all four units. T h e rece ivers have nar row threshold r e ­gions specif ied at ± 2 5 0 m V , w h i c h p r o ­v ide excel lent noise immuni ty .

The A m 2 6 S 1 0 has invert ing bus o u t ­puts , and the A m 2 6 S 1 1 has noninver t ing outputs, permit t ing full s y s t e m des ign flexibility. The A m 2 6 S 1 0 is a h igh-per for ­

m a n c e plug- in r e p l a c e m e n t for the 5 5 / 7 5 1 3 8 .

T h e c i rcui ts a r e ava i lab le in plast ic-mo lded D I P s . h e r m e t i c D I P s , and flat-p a c k s , in c o m m e r c i a l - and m i l i t a r y - t e m ­pera tu re r a n g e s .

Pr ices for the A M 2 6 S 1 0 range f r o m $ 2 . 6 5 for t h e p l a s t i c - m o l d e d D I P to $ 1 3 . 8 0 for the h e r m e t i c f l a t - p a c k , in 100-uni t lots.

For fur ther in format ion , contac t A d ­v a n c e d M i c r o D e v i c e s , Inc . , 9 0 1 T h o m p ­son PI . , S u n n y v a l e , Calif . 9 4 0 8 6 .

Circle No. 49 on Reader Service Card

D/A converter under $10 is useful for general-purpose and multiplying applications

Uni t -pr iced at $ 9 . 9 0 for the plast ic , 16-pin D I P , 8-bit unit, and $ 1 9 for the 10-bit vers ion , this cur rent -output D / A converter ser ies is d e s i g n e d to c o m p e t e in size and pr ice with I C - t y p e conver te rs .

The D A C 3 3 1 - 8 a n d the D A C 3 3 1 - 1 0 fea ture l ineari t ies of 0 . 2 and 0 .5 percent ,

respect ive ly . Stabil i ty is better than 1 to 2 p p m / ° C for l inearity over 0 to + 7 0 ° C . T h e C M O S swi tches use less than 2 0 m W of power .

Other speci f icat ions inc lude l inearity of ± 1 / 2 LSB, feedthrough of 0.1 percent a t 1 0 0 k H z , and an output -vo l tage c o m p l i ­

a n c e of 0 .1 volts at a n output current establ ished by the r e f e r e n c e vol tage d i ­vided by 2 5 i 2 . Fu l l - sca le T C is typically 10 p p m / ° C . T h e c o n v e r t e r s a re compat ib le with T T L / C M O S levels .

Del ivery is f r o m s tock to two w e e k s .

Contact Hybr id S y s t e m s C o r p . , 2 2 Third

Ave . , Bur l ington, M a s s . 0 1 8 0 3 .

Circle No. 50 on Reader Service Card

Low-cost multifunction converter multiplies and divides with 0.25-percent accuracy

This mult i funct ion conver te r of fers a low-cost solution to m a n y a n a l o g s ignal -convers ion p r o b l e m s . Sel l ing for $ 2 3 . 5 0 in hundreds ( 1 - 2 4 , $ 3 2 ; 2 5 - 9 9 , $ 2 8 ) the mode l 4 3 0 2 mult ipl ies a n d divides with a typical a c c u r a c y of 0 . 2 5 p e r c e n t .

The genera l t ransfer funct ion is

E0 = V , ( £ ) '

w h e r e Vx, Vy, and Vz refer to the input vo l tages that a r e appl ied to p r o d u c e E 0 . T h e exponent m is resistor p r o g r a m m a b l e a n d can be var ied f r o m 0 .2 to 5 .0 . By m a k i n g dif ferent uses of t h e t ransfer funct ion, the 4 3 0 2 c a n p e r f o r m the f u n c ­t ions of mul t ip l icat ion, division, s q u a r e rooting, squar ing, the squar ing of rat ios, a n d the raising of rat ios to arbi t rary p o w ­e r s . With the addit ion of ac t ive and p a s ­

sive c o m p o n e n t s , t r u e - r m s computa t ions , vector s u m s , s ine , cos ine , or a rc tangent convers ion funct ions m a y be p e r f o r m e d .

Typical a c c u r a c i e s e x p r e s s e d as a per­cent of fu l l -sca le output a r e : multiply or divide, ± 0 . 2 5 ; s q u a r e , ± 0 . 0 3 ; square root, ± 0 . 0 7 ; s ine, ± 0 . 5 ; cos ine , ± 0 . 8 ; and a r c t a n g e n t , ± 0 . 6 .

For fur ther in format ion , contac t Burr-Brown R e s e a r c h C o r p . , In ternat iona! Air­port Industr ia l P a r k , T u c s o n , Ariz . 8 5 7 3 4 .

New product applications 8 3

Circle No. 51 on Reader Service Card

New product applications Silicone encapsulant insulates high-voltage power supplies, while reducing size and weight

This si l icone e l a s t o m e r c a n be poured into h igh-vo l tage power -supp ly enc lo ­sures , w h e r e , upon cur ing , it fully insu­la tes the c i rcui t ry . T h e rubbery e n c a p s u ­lant c a n be cu t a w a y to e x p o s e de fec t ive c i rcui ts for repa i r . N e w mater ia l is poured into the void to r e e n c a p s u l a t e the re ­pa i red unit.

Being rubbery , the cured encapsu lan t protects the c i rcui t ry against m e c h a n i c a l s h o c k and a c c o m m o d a t e s any di f ferent ia l t h e r m a l e x p a n s i o n or cont rac t ion b e t w e e n c ircui t c o m p o n e n t s . It protects circuitry f r o m mois ture a n d is stable f r o m - 6 0 to + 2 0 0 ° C .

In one i n s t a n c e , t h e resil ient e l a s t o m e r cut the size a n d w e i g h t of a i r - insulated dc p o w e r suppl ies by m o r e than two thirds.

Oi l , inert g a s , and epoxy h a d also b e e n c o n s i d e r e d , but w e r e r e j e c t e d b e c a u s e of the possibil ity of oil l e a k a g e , loss of t h e g a s s e a l , or e r ra t ic p e r f o r m a n c e in t h e c a s e of the epoxy.

T h e si l icone e n c a p s u l a n t , k n o w n a s Sy lgard 1 7 0 A & B , is used o n h igh -vo l tage p o w e r suppl ies with outputs up to 1 0 0 k V as in the e x a m p l e just m e n t i o n e d . A p ­prox imate ly 3 .6 kg of the m a t e r i a l is r e ­qui red for a 1 0 0 - k V power supply. A t w o -part l iquid s y s t e m , the e n c a p s u l a n t is m ixed in t h e proper proport ion and then d e a e r a t e d in a v a c u u m c h a m b e r for t e n m i n u t e s . Cer ta in circuit c o m p o n e n t s a r e c o a t e d with a spec ia l p r imer for m a x i ­m u m a d h e s i o n of the e l a s t o m e r . N o r m a l l y the e l a s t o m e r is a l lowed to c u r e over -

D e a e r a t e d si l icone is p o u r e d into a 1 0 0 - k V p o w e r supply. T w o fully e n c a p s u ­lated units a r e s e e n at right.

night at r o o m t e m p e r a t u r e , a l though c u r e c a n be a c c e l e r a t e d by hea t ing .

C o n t a c t D o w Corning C o r p . , M i d l a n d , M i c h . 4 8 6 4 0 .

Circle No. 52 on Reader Service Card

Function module contains high-speed charge/sample-hold amplifiers

Model 9 0 8 1 is a smal l ( 5 . 0 8 - by 2 . 5 4 -by 1 . 2 7 - c m ) funct ion m o d u l e that c o n ­ta ins h igh-speed c h a r g e and s a m p l e - h o l d ampl i f iers . T h e c h a r g e ampl i f ier has a fu l l -scale c h a r g e input of 10 p i c o c o u -lombs and a h i g h - s p e e d swi tch for reset ­t ing that c o m p l e t e l y resets the c h a r g e ampl i f ier in less t h a n 3 0 ns. T h e c h a r g e -ampl i f ier sec t ion is fo l lowed by a high­s p e e d s a m p l e - h o l d ampl i f ie r (70 -ns m a x i m u m s a m p l i n g t i m e to a c q u i r e the

10-vol t output of the c h a r g e ampl i f ie r ) with a 10-volt fu l l -scale output vo i tage , a n d a n internal ana log swi tch .

T h e 9 0 8 1 m o d u l e is d e s i g n e d for use with photosens i t ive dev ices , c h a r g e - o u t ­put t r a n s d u c e r s , and c u r r e n t - s o u r c e d e ­v ices in cont ro l , m e a s u r e m e n t , and d a t a -acqu is i t ion s y s t e m s .

Addi t ional speci f icat ions inc lude a 1 0 - M H z m a x i m u m c lock f r e q u e n c y , a ± 1 0 - v o U / m s m i n i m u m output slew ra te ,

TTL compat ib i l i ty , and o p e r a t i o n f r o m ± 1 5 - v o l t supply lines. T h e 9 0 8 1 has a nA m a x i m u m of input bias c u r r e n t , a n d a m a x i m u m input offset of ± 1 m V .

Output speci f icat ions inc lude m a x i m u m load cur ren t of 5 m A , and m a x i m u m offset vo l tage of ± 1 m V .

T h e 9 0 8 1 is avai lable f r o m stock at $ 1 4 4 e a c h (single-unit quantifies).

For further information contact Optical Electronics, Inc., P.O. Box 1 1 1 4 0 , Tucson, Ariz. 8 5 7 3 4 .

Circle No. 53 on Reader Service Card

Spectrum's hardware review For m o r e in format ion on the fol lowing new p r o d u c t s , c i rc le

n u m b e r s on the r e a d e r serv ice ca rd cor responding to b racke t n u m b e r s .

T T L / C M O S - c o m p a t i b l e logic p r o b e with built - in pulse counter , A i k e n w o o d C o . [ 5 5 ] ; 12 -b i t , $ 1 5 9 D / A c o n v e r t e r in a smal l m o d u l e ( 5 1 by 5 1 by 1 0 m m ) sett les to 0 .01 p e r c e n t in 2 M S , Ana log D e v i c e s , Inc . [ 5 6 ] ; F o u r t e e n - d e c a d e ( 0 . 5 - o h m to 1-kS2) resistor box h a n d l e s 2 9 . 5 a m p e r e s at 7 volts a c / d c , Azar A s s o ­c ia tes [ 5 7 ] ; L o w - c o s t ( $ 1 9 in 1 0 0 s ) r m s - t o - d c c o n v e r t e r wi th 0 . 2 - p e r c e n t a c c u r a c y , B u r r - B r o w n R e s e a r c h C o r p . [ 5 8 ] ; Low-cost 1 5 0 - w a t t C 0 2 laser for industrial app l i ca t ions , C o h e r ­ent Radiat ion [ 5 9 ] ; 25<r ( % - i n - d i a m e t e r ( 0 . 9 5 - c m ) c e r m e t t r i m ­m e r s , C T S C o r p . [ 6 0 ] , A 1 6 - p i n , $ 1 1 , 8-bit D / A c o n v e r t e r , C y c o n , inc . [ 6 1 ] ; $ 1 2 4 opt ical e n c o d e r inc ludes all e l e c t r o n i c s , D a t a T e c h n o l o g y , Inc . [ 6 2 ] ; A $ 2 2 9 12-bit 4 - M S A / D c o n v e r t e r , D a t e l S y s t e m s , Inc . [ 6 3 ] ; H i g h - t e m p e r a t u r e p i e z o e l e c t r i c t r a n s ­d u c e r m e a s u r e s d y n a m i c p r e s s u r e f luctuat ions f r o m 0 . 0 1 to 5 0 0 ps i , E n d e v c o [ 6 4 ] ; 1 0 2 4 - b i t d y n a m i c P M O S 1 1 0 3 R A M wi th 1 2 0 - n s a c c e s s t i m e , Fairchi ld C a m e r a & I n s t r u m e n t Corp . [ 6 5 ] ; 2 5 6 - b y - 4 s ta t ic N M O S R A M s a r e pr iced d o w n to 1 0 2 4 - b y - 1 2 1 0 2 - t y p e l e v e l , Intel Corp . [ 6 6 ] ; C o m m e r c i a l l y ava i lab le 1 0 0 - 1 4 0 / 2 0 0 - 2 8 0 - v o l t a c sol id-state relay w o r k s f r o m 4 0 0 - H z inputs, In te rna t iona l Rect i f ier C o r p . [ 6 7 ] ; C M O S m i c r o p r o c e s s o r

e x e c u t e s D E C P D P - 8 / E instruct ion set , Intersi l , Inc . [ 6 8 ] ; C o m ­merc ia l l y ava i lab le a rgon laser wi th IR light, Lexe l C o r p . [ 6 9 ] ; M i n i a t u r e a d j u s t a b l e p n e u m a t i c sensor detects p r e s s u r e s as low as a f rac t ion of a n inch in w a t e r , M i c r o Pneumat ic Logic , Inc . [ 7 0 ] ; $ 2 . 5 0 , 1 -oz ( 2 8 . 3 5 g r a m s ) proximity sensor o p e r a t e s 1 0 0 k t i m e s per s e c o n d , M i c r o S w i t c h , Div. of H o n e y w e l l [ 7 1 ] ; M a ­c r o a s s e m b l e r p r o g r a m s for In te l m i c r o p r o c e s s o r s , M i c r o t e c [ 7 2 ] ; 1 6 - k b P M O S R O M a c c e s s e s in 6 0 ns, M o s t e k C o r p . [ 7 3 ] ; B r o a d b a n d C A T V I C ampl i f ie rs offer low-noise p e r f o r m a n c e , M o t o r o l a Inc . [ 7 4 ] ; P in- for -p in r e p l a c e m e n t for In te l 's 2 - k b E R O M , Na t iona l S e m i c o n d u c t o r Corp . [ 75 ] ; D u a l - i n - l i n e - p a c k ­a g e d prec is ion w i r e w o u n d resistors , R C D Corp . [ 7 6 ] ; M i n a t u r e O E M p a p e r - t a p e p u n c h with h igh s p e e d , R E M EX, a unit of Ex-C e l l - O Corp . [ 7 7 ] ; A new c o n c e p t in w i r e - w r a p p a b l e c o n t a c t s , S c a n b e , C a n o g a Industr ies [ 7 8 ] ; Tiny ( 3 . 1 6 by 2 . 0 2 by 0 . 9 5 c m ) , 9 0 - p e r c e n t ef f ic ient 2 4 - p i n d c / d c conver te rs p o w e r up to 25 I C s , S e m i c o n d u c t o r Circui ts , Inc . [ 7 9 ] ; N d : Y A G laser o p e r ­a ted up to 4 0 0 p u l s e s / s , G T E Sy lvan ia , Inc. [ 8 0 ] ; A c sol id-state re lays provide 6 0 0 - v o l t p e a k t rans ient immuni ty , T e l e d y n e R e ­lays [ 8 1 ] ; L inear -posi t ion 5 - o h m / m i l t ransducer w i t h 5 - y e a r g u a r a n t e e , U n i m e a s u r e [ 8 2 ] ; 8 - to 1 2 - G H z v a r a c t o r - t u n e d V C O de l ivers 5 m W m i n i m u m , W a t k i n s - J o h n s o n C o . [ 8 3 ] ; Equa l - r ip ­p le , a r b i t r a r y - t i m e - d e l a y m i c r o w a v e f i l ters, W a v e c o m [ 8 4 ] .

8 4 I E E E spectrum S E P T E M B E R 1975