MULTILANE DIGITAL SAMPLING OSCILLOSCOPE FEATURES & … · Compliance Test Suite and the Equalizer Tap Calibration tool, which uses a DSO to ... VEC = Vertical Eye Closure in dB. NRZ

MULTILANE DIGITAL SAMPLING

OSCILLOSCOPE

FEATURES & SPECS

JULY 2016

ML-DSO | Features & Specs

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The Multilane Digital Sampling Scope (ML-DSO) is an Equivalent-Time Sampling Oscilloscope

provided by Multilane Inc. (www.multilaneinc.com)

The DSO comes in multiple variants. Single channel electrical and optical variants have a small

form factor and are highly portable, while four channel flavors are also available in cPCI format. The DSO

hardware and features may appear integrated within other Multilane devices as well such as the time

domain analyzer (ML-TDA).

This document is intended to provide an overview of the DSO features, getting into some

technical details for clarifying various measurements and test capabilities.

http://www.multilaneinc.com/


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TABLE OF CONTENTS

OVERVIEW ...................................................................................................................................................... 4

SUPPORTED MEASUREMENTS ........................................................................................................................ 5

NRZ EYE AMPLITUDE MEASUREMENTS ................................................................................................................... 5

NRZ EYE TIME MEASUREMENTS ............................................................................................................................ 6

NRZ EYE MASK MEASUREMENTS ........................................................................................................................... 7

PATTERN AMPLITUDE MEASUREMENTS ................................................................................................................... 7

PATTERN TIME MEASUREMENTS ............................................................................................................................ 8

NRZ JITTER DECOMPOSITION / EYE WIDTH BY BER ................................................................................................... 8

NRZ NOISE DECOMPOSITION / EYE HEIGHT BY BER .................................................................................................. 9

OPTICAL MEASUREMENTS ................................................................................................................................... 11

PAM 4 MEASUREMENTS .................................................................................................................................... 14

FREQUENCY DOMAIN MEASUREMENTS .................................................................................................................. 15

DSO ARCHITECTURE ...................................................................................................................................... 17

SOFTWARE FILTERING .................................................................................................................................. 19

APPENDIX A: DSO PRODUCT FAMILY ............................................................................................................ 21

APPENDIX B: CORRELATION REPORT – TIME DOMAIN MEASUREMENTS .................................................... 22

APPENDIX C: CORRELATION REPORT – S21 MEASUREMENT ....................................................................... 23


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OVERVIEW

The Multilane Digital Sampling Oscilloscope is a fully-integrated instrument that automatically

performs accurate eye-diagram analysis to characterize the quality of transmitters and receivers.The

“DSO” implements a statistical under- sampling technique with comprehensive software libraries for eye

measurements, jitter analysis and processing of NRZ data. The DSO is offered in four lane and single lane

form factors for optical and/or electrical inputs.

DSO Hardware is compact and highly responsive. It is an

Equivalent Time Sampling Oscilloscope which supports up to 256K

samples per acquisition, where each sample can have amplitude

within 4096 different levels (12 bit resolution). ETS Sampling rate is

usually between 50 MHz and 100 MHz. The DSO is available in 32 and

50 GHz variants, enabling high-bit rate eye captures.

DSO Software and tools enable various features including the following:

An extensive set of measurements: eye, masks, pattern, PAM-4, optical inputs, and frequency

domain. Key features are Mask Margin, Jitter/Noise decomposition, BER and measuring insertion

loss S21/S12 or Sdd21/Sdd12

Software Filtering: CTLE, moving averages, S21 De-Embedding or Emulation, FFE, DFE, Bessel

Thomson

All functions are available as APIs and enable easy integration of the DSO in any automated

measurement environment under supporting

Windows or Linux. These APIs are extensively

used in production ATE testing

Rich Windows GUI with graphically detailed

eye diagrams, histograms and bathtub curves

Examples of tools that integrate with the

DSO. These tools from Multilane rely on the

DSO for some functionality, such as the

Compliance Test Suite and the Equalizer Tap

Calibration tool, which uses a DSO to

adaptively adjust a hardware equalizer for

desired signal shaping.


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SUPPORTED MEASUREMENTS

The DSO measurements can be divided into various groups, some related to eye diagrams,

others to patterns, some related to NRZ coding, and others to PAM4, in addition to advanced

measurements like Jitter/Noise decomposition and S21 insertion loss measurement.

NRZ EYE AMPLITUDE MEASUREMENTS

Histogram

The amplitude histogram is available in the DSO GUI. It shows

the amplitude distribution of the signal.

Top

Median value of the top portion of the amplitude histogram.

Base

Median value of the bottom portion of the amplitude

histogram.

Voltage

Amplitude

The difference between top and base of an eye.

One and

Zero level

The average amplitude at 20% around the center of the open

eye. The percentage around the eye center is configurable for

the DSO API.

Eye

Amplitude

The difference between One level and Zero level of an NRZ eye.

Min The minimum amplitude value.

Max

The maximum amplitude value.

Peak to Peak

The difference between the max and the min amplitude values


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Eye Height

Eye Height is the vertical opening of the eye measured.

Crossing

percentage

The amplitude of the crossing level where we transition from

zero to one or vice versa.

SNR

The signal to noise ratio is a ratio of the difference between one

level and zero level relative to the noise present at both levels.

VEC

VEC = Vertical Eye Closure in dB.

NRZ EYE TIME MEASUREMENTS

Fall Time

The mean transition time of the data on the downward slope of an

eye diagram between 2 defined thresholds e.g. 80% and 20%.

Rise Time

The mean transition time of the data on the upward slope of an eye

diagram between 2 defined thresholds e.g. 20% and 80%.

Eye Width

The time between the latest possible occurrences of one eye Crossing

to the earliest possible occurrence of the next crossing

Jitter

Jitter is defined as a measure of the short-term variations of the

significant instances of a digital signal from its ideal position on the

time axis. In other words, ideally, an edge should always land at the

same position on the time axis. In the real world, the edge is

sometimes a little early, sometimes a little late. This is jitter,

summarized as the width at the eye crossing. The jitter peak to peak

and rms values are measured and displayed in picoseconds.


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NRZ EYE MASK MEASUREMENTS

The user can create and save eye masks as needed for any of the

configurations explained below. The mask specified can also be allowed to

expand calculating the mask margin. For calculating mask margin, the user

may specify either a target hit ratio (BER) or a target number of failing

points. Additionally, the DSO has various standard masks predefined for

easy access: 100Gbase-SR, LR, STM-1, STM-4, STM-16, Gb Ethernet, Fiber

Channel (1x), Fiber Channel (2x, 4x), Fiber Channel (8x), Fiber Channel

(10x), 10 Gb Ethernet, 100GBASE-LR4, PSM4, etc.

PATTERN AMPLITUDE MEASUREMENTS

VMA

The voltage modulation amplitude of a pattern displayed in

mV.

Emphasis

In high speed digital transmission, pre and post emphasis

are used to improve signal quality at the output of a data

transmission.

http://www.answers.com/topic/signal-integrity

http://www.answers.com/topic/data-transmission




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PATTERN TIME MEASUREMENTS

Emphasis

Emphasis width (in PS) is measured as well for pre and post

emphasis.

Pattern

Rise Time

The rise time value is the average value of all the rise time

of all the sequence of bits.

Pattern Fall

Time

The fall time value is the average value of all the fall time

of all the sequence of bits.

NRZ JITTER DECOMPOSITION / EYE WIDTH BY BER

The signal jitter and eye width can be analyzed statistically for pattern lengths up to PRBS 13, to

show estimates of Jitter and EW for specific target Bit Error Rates (BER).While locked to the pattern, the

pattern signal is extracted in high resolution. It is then subjected to filters that remove additive white

Gaussian noise and random jitter which usually has a Gaussian distribution. The two signals before and

after filtering are then compared and processed in order to come up with two key jitter components:

1- Deterministic Jitter: This represents the bounded jitter components following the Dual-

Dirac model.

2- Random Jitter: This represents the unbounded / Gaussian distributed components of the

Dual-Dirac model.

Once deterministic and random jitter is measured, they are used to calculate different other

measurements:


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1- Total Jitter (BER): This is the Total Jitter expected for a given target Bit Error Rate (BER). This

value is calculated as:

TJ(BER) = DJ + RJ pp (BER)

TJ(BER) = DJ + K(BER) * RJ RMS

Total Jitter (J2): TJ(BER) for BER = 2.5 x 10-3

Total Jitter (J9): TJ(BER) for BER = 2.5 x 10-10

2- Eye Width (BER): Equivalent to the time of one bit period minus TJ (BER).

Note that K(BER) is a constant factor which is a function of the Bit Error Rate, derived by assuming

random jitter has a Gaussian Distribution.

NRZ NOISE DECOMPOSITION / EYE HEIGHT BY BER

The Vertical/Amplitude noise in a signal is decomposed at the same area around the eye center which is

used to measure the one and zero level, typically at 20%. Noise is decomposed into:

A- Deterministic Noise = Deterministic Top + Deterministic Base

i. Deterministic Top = One Level minus the deterministic lower bound of points used

when calculating one level.

ii. Deterministic Base = Deterministic upper bound of points used when calculating

zero level minus zero level.

The upper and lower bounds are calculated as the maximum and minimum points in the

20% area after subjecting the signal to a filter that removes all additive white Gaussian

noise.

B- Random Noise (rms): This is calculated as the standard deviation of the additive white

Gaussian noise.


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Once Deterministic and random noise are measured, they are used to calculate other measurements:

1- Total Noise (BER): This is the Total Noise expected for a given target Bit Error Rate (BER). This

value is calculated as:

TN(BER) = DN + RN pp (BER)

TN(BER) = DN + K(BER) * RN rms

2- Eye Height (BER): Equivalent to the time of one bit period minus TN (BER).

Note that K(BER) is a constant factor which is a function of the Bit Error Rate, derived by assuming

random noise has a Gaussian Distribution.


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OPTICAL MEASUREMENTS

AOP – Average Optical Power

Measured as 𝑂𝑛𝑒 𝐿𝑒𝑣𝑒𝑙 +𝑍𝑒𝑟𝑜 𝐿𝑒𝑣𝑒𝑙

2

OMA – Optical Modulation Amplitude

The equivalent of Eye Amplitude for electrical, measured as (One Level – Zero Level)

Extinction Ratio

Measured as 10 𝐿𝑜𝑔10 𝑂𝑛𝑒 𝐿𝑒𝑣𝑒𝑙

𝑍𝑒𝑟𝑜 𝐿𝑒𝑣𝑒𝑙

Mask Margin

Mask Margin calculation is available for optical measurements and it is very similar to Electrical mask

margin calculation.

SPECTRAL COMPENSATION TO COMPARE OPTICAL PLUG-INS

The above optical measurements are key metrics for characterizing the TX outputs of E-O

transceivers. Different Optical receivers or optical sampling scope plug-ins will return different Mask

Margin test results for the same input signal. The channel response of the Optical receiver (Insertion

Loss variation, and Group Delay variation) are the main reason that cause varying mask margin results

from the same signal.

DSO Software Filters can be used to spectrally compensate for the channel response variation of

different O/E, rendering signals from different O/E testable and comparable. In manufacturing test

application, measurement repeatability and accuracy are extremely critical. Historically, different optical

plug-ins from the same vendor yielded different results for measurements performed on the same input

signals.

Spectral compensation using DSP yields uniform measurements, as well as a wider dynamic

range of the optical measurements. Spectral shaping has limits however, of the maximum pattern it can

capture, in relation to the memory capture of the scope, and the test time.

Example follows on next page.


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MEASUREMENTS BEFORE FILTERING

The following are step responses, and eye / mask measurements at 25.78125Gbps of three different

receivers. Note the ringing in the time domain.

Vendor B

Measurements Unit Current

Jitter P-P Ps 5.3

Mask Margin % 45

Vendor A2


Jitter P-P Ps 9

Mask Margin % 0

Vendor A1


Jitter P-P Ps 6.2

Mask Margin % 0

Vendor C


Jitter P-P Ps

9.39

Mask Margin % 15.8

Eye Measurement Impulse Response


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MEASUREMENTS AFTER FILTERING FOR SPECTRALLY CORRECTED SIGNALS

The screenshots and measurements below are of the 3 difference O-E Receivers that have been

spectrally compensated to match the insertion loss of Vendor B.

Vendor A2


Jitter P-P Ps 4.85

Mask Margin % 51.39

Vendor A1


Jitter P-P Ps 4.39

Mask Margin % 55.01

Vendor C


Jitter P-P Ps 5

Mask Margin % 48.22

PN9-Corrected with Vendor B as REF


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PAM 4 MEASUREMENTS

PAM 4 measurements implemented in the DSO software follow the Optical Internetwork

Forum’s (OIF) requirements. Multilane is an active member of the Optical Internetworking Forum and is

updating these measurements as new rules/requirements are being decided.

Measurements can be split in two categories:

A- Measurements that analyze PAM 4 eyes in eye mode and can work up to PRBS 31

B- Measurements that depend on the pattern signal and can work up to PRBS 13. Note that

applying any software filters on the signal would require pattern lock as well and is therefore

also limited to PRBS13

PAM 4 EYE MEASUREMENTS (UNRESTRICTED PATTERN LENGTH)

a. AVupp, AVmid, AVlow: Vertical Amplitudes

b. Vupp, Vmid, Vlow: Vertical Eye Openings

c. Hupp, Hmid, Hlow: Horizontal Eye Openings

d. VEC: Vertical Eye Closure

PAM 4 PATTERN MEASUREMENT - TARGET BER (UP TO PRBS 13)

For the previously discussed PAM4

measurements, AVxxx, Vxxx, & Hxxx, we are currently

reading the measurements for an equivalent BER of 1e-5

from a single capture if taking 262K samples per UI. We

estimate up to BER =1e-15 using Gaussian statistics when

locked to the pattern, which is currently limited up to

PRBS13.


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FREQUENCY DOMAIN MEASUREMENTS

The Multilane DSO is now capable of measuring insertion loss S-Parameters, as will be

highlighted in this section. Depending on how the DSO is set up, one should be able to measure either of

Sdd21, Sdd12, S21, S12, S43, S34, etc.

The only difference between all the above is:

1- Single-ended vs. differential connection

2- The direction in which you have connected the DUT for which you are measuring S-Parameters

3- The ports which you have used when connecting the DUT in case of a single-ended connection

The approach used consists of these steps:

1- Define your Circuits:

a. Main Circuit: Contains the DUT for which the S-Parameters are to be measured

b. Reference Circuit:

i. Excludes the DUT whose S-Parameters need to be measured

ii. Is as identical as possible to the Main Circuit, except for the DUT

iii. May require an additional component, such as an adapter, for non-insertable

through connections

2- Setup your PPG:

a. PRBS9

b. Maximum Bit-Rate supported (For Maximum resolution in your result).

c. Cleanest Eye Possible. This sometimes translates to Maximum Amplitude in order to

maximize Signal-To-Noise Ratio. However, be careful not to exceed the maximum

amplitude supported by your Multilane DSO without using attenuators.

Kindly note: PPG settings and amplitudes should not be altered after this point otherwise

the calibration will be void.

3- Capture your Reference Signal: When having the cleanest PPG settings as above, and your

Reference Circuit connected, run the DSO S-Parameter Setup Wizard to capture reference data.

4- Without altering any of the PPG settings, connect your Main Circuit, basically just connect the

DUT where needed to switch from ‘Reference Circuit’ to ‘Main Circuit’, and run in S-Parameter

mode, you should now be able to see the S21 Insertion Loss Magnitude drawn on the screen.


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For a constant PPG Source Signal, S21 Is calculated using the equation:

Frequency Response of DUT = FFT (Main Circuit Signal) / FFT (Reference Circuit Signal)

5- The insertion loss can be saved in external .s2p and .DsoCirc files. These files contain both

magnitude and phase information. These files with their magnitude and phase information can

later be used in the DSO Software for de-embedding or emulating the DUT or they can be

exported for display on a VNA; this is shown in appendix B.


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Loss at Nyquist

Loss at Nyquist frequency, half the baud rate, is measured and displayed.

Frequency Response Masks

Masks are available for checking the validity of the frequency response, supporting custom and

predefined masks.

DSO ARCHITECTURE

This section describes the different layers of the DSO and how they interact with each other to

make the functioning product.

HIGH-LEVEL

The DSO Software can be divided into GUI and API. The Software runs from any PC on the same

network as the DSO Device. The DSO Hardware contains a microprocessor, which in turn is controlled by

Firmware. The DSO device, consisting of firmware and hardware, is the receiving end of commands sent

out by the DSO Software, residing on a separate PC. The device then responds over Ethernet with the

data requested by the software including raw signal capture data, temperature reading, board ID and

serial number.

DSO GUI (C#.NET WinForm)

or Customer-Developed Frontend

DSO API (C++ Library, Windows / Linux)

Ethernet

DSO Device – Firmware – Hardware


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SOFTWARE ARCHITECTURE

The DSO Software consists of a front end and a C++ API. The C++ API is provided for both

Windows and Linux with sample front-end code that executes the API.

The front end code can typically be developed using any programming language. This is the

interface or application that the user interacts with. We support our customers getting started with the

API and provide sample code when available, depending on the language used by the customer. We

have partners/customers using the DSO API with front-ends written in .NET Framework, C++, Python,

Labview, Verigy 93K SmarTest Environment and even Matlab.

In addition to the API, Multilane provides a full-featured GUI for use with the DSO. The DSO GUI

is a full featured front end developed by Multilane for Windows using C#.NET. In addition to

demonstrating API features, the DSO GUI also contains additional features not present in the API, such

as:

Detailed graphs and a user friendly interface, includes graph markers for manual validation of

measurements, and UI features such as easy ability to remember and switch between different

configurations, etc.

Experimental features and measurements and newly released features appear in GUI before the

API

Various graphical wizards necessary for generating configurations re-usable by the API, such as

software filters and simulation data

FIRMWARE

The firmware of the DSO exposes various functionalities including:

1- Retrieving sampled data from the DSO

2- Reading temperature

3- Reading diagnostic information:

a. Board ID

b. Serial Number

c. Firmware Revision

4- Reading/writing DSO Calibrations

5- Controlling the required PLL dividers to achieve a desired sampling frequency

6- Controlling features such as Clock Data Recovery in hardware flavors where CDR is available

7- Providing access to on-board EE-PROM memory used to saving board-specific details such as

the latest settings used when connecting to the board


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HARDWARE ARCHITECTURE

In summary, the DSO hardware consists of:

A Sampling Clock, connected to a Track and Hold (T/H), and an Analog to Digital converter (A-

to-D)

At the desired ETS sampling rate, the T/H will read an analogue voltage amplitude level,

convert it to digital using the A-to-D, which would end up as integer from 0 to 4095. This

integer is loaded into a FIFO.

A microprocessor is controlling/listening to the Ethernet, and when it receives specific

commands it dumps back over Ethernet the content of the FIFO, which are converted to

voltage amplitude levels by the DSO Software based on DSO Calibrations saved on the device

itself.

SOFTWARE FILTERING

Various filters are supported by the DSO Software. The DSO GUI can save the configured set of filters

into a single merged filter for use by the API. The API supports only one filter for performance reasons,

yet this filter can be easily prepared from the GUI as a combination of multiple filters together, which is

implemented through convolution. Software filtering in the DSO requires pattern lock and is supported

up to PRBS13.

Above filters are:


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1- Moving Average: This time-domain filter replaces each sample with the average of the nearest N

samples, N being the number of samples specified as the moving average window. This filter is

equivalent to a convolution with a square signal, which would be a sinc function in the

frequency domain.

2- Bessel Thomson: The Bessel Thomson low pass filter can be enabled for any desired filter order

and bandwidth relative to the connected signal bit rate.

3- S-Parameters can be used to generate de-embedding. We support .S4P files, .S2P files, as well as

the DSO proprietary .S21 files and DsoCirc files. DsoCirc files display a whole circuit allowing

users to either emulate or de-embed one or more components of the circuit

Figure: De-Embedding a 16 inch Xilinx trace

4- CTLE Filters are supported, where coefficients can be calculated on the go for desired total gain,

or entered manually for specific settings to apply required conditions.

5- FFE and DFE Filters are also supported.


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APPENDIX A: DSO PRODUCT FAMILY

ML4006: Digital Sampling Oscilloscope that can be ordered as

either a 32 GHz or a 50 GHz bandwidth variant. The ML4006 is

typically used to characterize the quality of transmitters and

receivers, implementing a statistical under-sampling technique

with comprehensive software libraries used for eye measurements,

jitter analysis and processing of NRZ and PAM4 data.

ML4005C: 32 GHz Digital Sampling Oscilloscope

and 9.5 GHz wideband optical reference receiver

with differential electrical data inputs.

ML4005D: 32 or 50 GHz Digital Sampling

Oscilloscope and 25GHz wideband optical reference

receiver with differential electrical signal inputs (AC

coupled) and a DC coupled O/E for optical

measurements.

ML4025: 4 channel Digital Sampling

Oscilloscope, automatically performing accurate

eye-diagram analysis at 32GHz or 50GHz to

characterize the quality of transmitters and

receivers, implementing a statistical under-

sampling technique with comprehensive software

libraries used for eye measurements, jitter

analysis and processing of NRZ/PAM4 data.


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APPENDIX B: CORRELATION REPORT – TIME DOMAIN MEASUREMENTS

This section highlights the accuracy of key DSO measurements when compared to the

Oscilloscope of another leading vendor, henceforth referred to as ‘Vendor A’. For this test, a PRBS31

signal was transmitted from the ML4009-JIT at 650 mV peak to peak amplitude. With PTB disabled, two

signals were compared at 25.78125 Gb/s. The first was unstressed, and the second was modulated with

1024 taps of sinusoidal jitter at a PM frequency of 5 MHz. Each measurement contained 600,000 points.

1- UNSTRESSED EYE RESULTS

Vendor A DSO

Parameter Vendor A, current

Vendor A, min

Vendor A, max

DSO, average

DSO, min DSO, max

Fall Time 14.840 6.020 12.352 14.02 13.97 14.08

Rise Time 14.420 14.140 14.7 12.88 12.80 12.94

Eye Amplitude 667 351 676 670.80 662.54 680.99

P-P Jitter 9.52 9.82 10.22 9.46 9.44 12.36

2- STRESSED EYE RESULTS

Vendor A DSO

Parameter Vendor A, current

Vendor A, min

Vendor A, max

DSO, average

DSO, min DSO, max

Fall Time 13.867 13.578 14.156 14.30 14.21 14.45

Rise Time 14.156 13.722 14.444 12.83 12.66 12.95

Eye Amplitude 670 669 674 672.83 666.25 679.35

P-P Jitter 14.44 11.844 15.67 12.85 11.40 14.43


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APPENDIX C: CORRELATION REPORT – S21 MEASUREMENT

Various circuits were measured to determine how the DSO measurement compares to a VNA.

The results are presented below.

DIRECT ATTACH CABLE INSERTION LOSS MEASUREMENT

One of the frequent applications of insertion loss measurement using a DSO is the production

testing of QSFP Direct Attach Cables (DAC). One major advantage of using the DSO instead of a VNA is

the ability to capture Sdd21 of all 4 channels at once without moving cables around – in addition to cost

savings, since a 4-port VNA is generally much more expensive than a DSO.

DAC insertion loss is measured using 2 MCBs and a DSO or a VNA

First we shall measure the DAC using the DSO then we will repeat the measurement using the VNA and

finally we shall export the DSO s2p file for display on the VNA side-by-side with the VNA curve.

Once all 16 cables are connected, the DSO can take all measurements at once, see trace below.

Automated marker and mask functions will give you go/no go results within seconds.


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Insertion loss traces of all 4 lanes of a DAC acquired with one click

The traces above show the insertion loss of the DAC cable under test alone. The MCBs and cables have

been de-embedded. These traces are next saved as .s4p and loaded in an N5225A VNA to compare the

accuracy. Results are presented for one of the channels in the following capture.

In the above figure, DSO IL data is exported to the VNA (Green). The brown curve is the VNA native IL trace. Shown here is channel 1


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About MultiLane SAL MultiLane SAL is leading developer of high speed instruments and interconnects test modules for 10, 40, and 100Gbps of SerDes and high speed IO for the semiconductor and cloud computing infrastructure. Products includes BERTs, Scopes, and a host of MSA Compliant development tools for CFP, CFP2, SFP, SFP28, QSFP, zQSFP modules. MultiLane’s products are used to test semiconductors, AOC, electro-optical modules and blades. MultiLane operates out of Houmal Technology Park in Lebanon, and has been offering leading edge technology and products to Tier-1 equipment suppliers globally. Visit www.multilaneinc.com

Worldwide Multilane SAL Houmal Technology Park 141 Main Road Houmal, Lebanon +961 5 941668 Website: www.multilaneinc.com Email: [email protected]

North America & Europe

MultiLane Inc 2000 Wyatt Drive, Suite 6 Santa Clara CA 95054, USA

+1 408890 2234

Asia MultiLane Asia Inc No. 18, Prosperity Rd. 2 Hsinchu Science Park, Taiwan +886-3-6686667



mailto:[email protected]

Documents

MULTILANE DIGITAL SAMPLING OSCILLOSCOPE FEATURES & … · Compliance Test Suite and the Equalizer Tap Calibration tool, which uses a DSO to ... VEC = Vertical Eye Closure in dB. NRZ