Teledyne SDA III User Manual

Operator's
Manual

SDAIII-CompleteLinQ
Software

SDAIII-CompleteLinQ Software Operator's Manual

© 2013 Teledyne LeCroy, Inc. All rights reserved.

Unauthorized duplication of Teledyne LeCroy documentation materials other than for internal sales and
distribution purposes is strictly prohibited. However, clients are encouraged to distribute and duplicate
Teledyne LeCroy documentation for their own internal educational purposes.

SDAIII-CompleteLinQ and Teledyne LeCroy are registered trademarks of Teledyne LeCroy, Inc. Windows
is a registered trademark of Microsoft Corporation. Other product or brand names are trademarks or
requested trademarks of their respective holders. Information in this publication supersedes all earlier
versions. Specifications are subject to change without notice.

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TABLE OF CONTENTS

SDAIII-CompleteLinQ Overview 3

Key Features 4
What's New in SDAIII-CompleteLinQ 4
Compatible Oscilloscope Models 5
Required Firmware 5

Getting Started with SDAIII-CompleteLinQ 6

How to Order SDAIII-CompleteLinQ Capabilities 6
Accessing SDAIII-CompleteLinQ 7
SDAFramework Dialog 8
LaneScape Comparison Mode 10
Quick View 12
Lane Configuration Process 13

Signal Inputs 15

Set Up Signal 15
Signal Dialog 16
Serial Data Inputs 17
Crossing Levels 17
Signal Types 18

Clock 19

Set Up Clock Recovery 19
Clock Recovery Dialog 19
PLL Setup 20
Clock Recovery Theory 23
Set Up Reference Clock 24

Eye Measurements 26

Eye Measurements Overview 26
Eye Dialog 27
Set Up Eye Diagram 27
Eye Diagram Configuration Dialog 28
Eye Modes 29
Mask Testing 29
Mask Margin 30
Eye Parameters Dialog 31
Eye Measurement Parameters 31
Eye Analysis Theory 34

Jitter Measurements 36

Set Up Jitter Measurements 36
Jitter Filter 39
Jitter Pattern Analysis 39
Jitter Track 42
Jitter Spectrum 42
Jitter Histogram Analysis 46

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Jitter Parameters 47

Vertical Noise Measurements 48

Vertical Noise Measurements Overview 48
Noise Filter 49
Noise Pattern Analysis 50
Noise Track 51
Noise Spectrum 52
Noise Histogram Analysis 52
Noise Parameters 53
Noise Measurement Theory 53

Crosstalk Measurements 55

Crosstalk Analysis 55

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SDAIII-CompleteLinQ Overview

The SDAIII-CompleteLinQ Serial Data Analysis package introduced with firmware version 6.9.0.x provides
comprehensive measurement capabilities for evaluating high-speed serial data signals.

SDAIII-CompleteLinQ builds on the power of SDAII, extending the analysis to up-to-4 lanes simul­taneously, and providing a "reference" analysis lane for comparison purposes. SDAIII-CompleteLinQ is
the single-lane version. Both packages are a signal integrity analysis framework, integrating capabilities
from the EyeDoctor II, VirtualProbe and Crosstalk packages. In this manual, SDAIII-CompleteLinQ will
often be used to refer to the underlying analysis "engine"

Like its predecessor SDAII, SDAIII-CompleteLinQ operates by rapidly processing a long signal acquisition.
For best results, acquisitions should be long enough to include at least 100,000 UI of the signal under test
(500,000 UI or more is optimal). By using long acquisitions, users can have the best statistics for accurate
measurements and be able to measure low-frequency periodic jitter components.

The calculation methodology in SDAIII-CompleteLinQ is the same as SDAII, with the addition of the Dual­Dirac "RjDirect" jitter calculation method. All jitter measurements, eye diagrams and analysis views are
based on comparisons of the arrival times of the signals edges to that of the underlying clock, which is
determined either via a software clock recovery algorithm or by measurement of a clock signal. Nothing
is measured relative to the trigger; as a result, measurements are not affected by trigger jitter.

SDAIII-CompleteLinQ can be purchased as part of the standard installation on new instruments or as an
upgrade to existing instruments. See How to Order SDAIII-CompleteLinQ Capabilities.

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Key Features

l Simultaneous analysis of up-to-four lanes of data (requires one of the LinQ options).

l Two overall types of measurements: eye pattern testing and comprehensive jitter analysis (includ-

ing random and deterministic jitter separation, and direct measurement of periodic jitter, DDj,
and DCD).

l Many plot types for jitter and eye diagram analysis, including eye diagram, IsoBER, DDj Plot, dig-

ital pattern, DDj Histogram, jitter track, PLL track, jitter spectrum (with peak annotation), spec­trum threshold, Pj Inverse FFT, jitter histogram, CDF, bathtub and Normalized Q-scale fit.

l Filtered jitter processes the time interval error trend versus time with a user-selectable band-pass

filter. This feature allows applying filters in addition to the high-pass filtering effect of the clock
recovery PLL, which is required for some serial data specifications.

l IsoBER displays the extrapolated lines of constant Bit Error Ratio down to the BER of interest on an

eye diagram.

l Quick View provides a shortcut displaying the eye diagram, TIE track, bathtub curve, jitter his-

togram, NQ-scale cursors, and jitter spectrum all on the screen at the same time.

l Fully-integrated multi-lane analysis framework with the SDAIII-CompleteLinQ LinQ family of

options, accessing features of the EyeDoctor II and VirtualProbe packages. (Single-lane analysis is
standard with SDAIII-CompleteLinQ.)

l Access to the new Reference Lane capability.

l When purchased with the Crosstalk or CrossLinQ package, access to advanced noise and crosstalk

measurements.

What's New in SDAIII-CompleteLinQ

Fully-integrated, Multi-lane Analysis Framework

The SDAIII-CompleteLinQfamily of software options begins with a configuration dialog that integrates all
the serial data analysis capabilities enabled on your oscilloscope. Buttons for emphasis, equalization, de­embedding and emulation are enabled with the EyeDoctor II package. The Noise and Crosstalk buttons
are enabled by the Crosstalk and CrossLinQ packages.

Multi-lane Serial Data Analysis

When ordering SDAIII-CompleteLinQ capabilities, you can enable up-to-4 lanes for analysis. Lanes can use
either single-ended or differential signals, or be directly cabled to the oscilloscope using probes or other
waveforms traces including zooms, math functions or memory traces. You can configure lanes to analyze
data from different inputs, or can utilize multi-lane analysis to perform different analysis on the same
data. (For example, all lanes could use channels 1 and 2 as the source data, with different configurations
for the jitter analysis, such as different jitter filter settings or jitter calculation methods.) Ifyou also use
EyeDoctor II, you can configure different equalization schemes on each lane.

Noise and Crosstalk Measurements

When purchasing either the SDAIII-CompleteLinQ-Crosstalk or SDAIII-CompleteLinQ-CrossLinQ package,
you have access to the Noise and Crosstalk measurements. This powerful measurement package char­acterizes vertical noise, providing insight into noise due to crosstalk or interference. The set of analysis
views is similar to what is found in SDAIII-CompleteLinQ jitter measurements, and includes residual noise

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track, noise spectrum, histogram and Q-fit, and noise measurements broken down into Tn (total noise),
Rn (random noise) and Dn (deterministic noise). The Crosstalk package includes the Crosstalk Eye, which
is an eye diagram based on noise analysis that depicts effects from noise aggressors more clearly than a
standard eye diagram. You can compare Crosstalk Eyes from 2 different lanes.

LaneScape Comparison Mode

When you enable multiple lanes (or one lane + the Reference lane), the oscilloscope automatically turns
on "LaneScape Comparison Mode". In this mode, all waveforms and traces for a single lane are displayed
in its own frame, which you can arrange into different "LaneScapes." You can choose to display one, two
or all LaneScapes at a time to meet your particular needs for comparing analysis results between lanes.

Spectral Rj Direct Jitter Calculation Method

SDAIII-CompleteLinQ includes the Spectral Rj Direct jitter calculation method. This method fixes Rj based
spectral analysis methods, and can return jitter results that compare more closely to results on oscil­loscopes from other manufacturers. See Understanding SDAIII-CompleteLinQ Jitter Calculation Methods
for more information.

Compatible Oscilloscope Models

The SDAIII-CompleteLinQfamily of software options is available on the WavePro/SDA/DDA 7 Zi/Zi-A,
WaveMaster/SDA/DDA 8 Zi/Zi-A, LabMaster 9 Zi-A and LabMaster 10 Zi oscilloscopes platforms.

Required Firmware

Your oscilloscope must be running firmware version 6.9.0.x or higher to support SDAIII-CompleteLinQ
and VirtualProbe. Firmware upgrades are available from www.teledynelecroy.com/support/downloads.

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Getting Started with SDAIII-CompleteLinQ

How to Order SDAIII-CompleteLinQ Capabilities

SDAIII-CompleteLinQcapabilities can be purchased in a variety of ways. See the product brochure on the
Teledyne LeCroy website for product names and additional ordering information, or contact your local
Teledyne LeCroy Customer Care Center.

New Oscilloscopes

SDA AND DDA MODELS

Basic SDAIII-CompleteLinQ capabilities—single-lane +reference lane, eye and jitter analysis—are deliv­ered standard with SDA/DDA 7 Zi/Zi-A and SDA/DDA 8 Zi/Zi-A oscilloscopes. To order advanced features,
attach any of the following suffixes to the scope prefix (e.g., SDA8Zi-<suffix>):

Crosstalk: Upgrades SDA or DDA models to also include noise and crosstalk measurements

LinQ:Upgrades SDA or DDAmodels to also include multi-lane eye and jitter analysis

CrossLinQ: Upgrades SDA or DDAmodels to also include multi-lane eye, jitter, noise and crosstalk anal-

ysis

CompleteLinQ: Upgrades SDA or DDAmodels to also include multi-lane eye, jitter, noise and crosstalk
analysis, and bundles in the EyeDoctor II and VirtualProbe packages.

NON-SDA AND DDA MODELS

Models in the WavePro 7 Zi/Zi-A, WaveMaster 8 Zi/Zi-A, LabMaster 9 Zi-A and LabMaster 10 Zi series can
be upgraded to include SDAIII-CompleteLinQ capabilities by ordering with the following suffixes (e.g.,
WM8Zi-<suffix>):

SDAIII: Enables single-lane +reference lane, eye and jitter analysis.

SDAIII-Crosstalk: Enables single-lane +reference lane, eye, jitter, noise and crosstalk analysis.

SDAIII-LinQ:Enables multi-lane eye and jitter analysis.

SDAIII-CrossLinQ: Enables multi-lane eye, jitter, noise and crosstalk analysis.

SDAIII-CompleteLinQ: Enables multi-lane eye, jitter, noise and crosstalk analysis, and bundles in the Eye-

Doctor II and VirtualProbe packages.

Upgrading Existing Oscilloscopes

Contact your local Teledyne LeCroy Customer Care Center for obtaining a quotation for upgrading pre­viously purchased oscilloscopes to include SDAIII-CompleteLinQ capability.

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Accessing SDAIII-CompleteLinQ

Access the SDAIII-CompleteLinQ by choosing Analysis>Serial Data to display the SDA Framework dialog
at the bottom of the screen.

The SDA Framework Dialog shows the overall flow for viewing and analyzing serial data. Each block in the
flow diagram is a button that, when touched, displays its corresponding dialog.

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SDAFramework Dialog

This SDAIII-CompleteLinQ Framework dialog is the main configuration screen for all serial data analysis. It
represents the overall flow for viewing and analyzing serial data, beginning with lane configuration at the
left, through Eye, Jitter, Vertical Noise and Crosstalk measurement at the right.

Each block in the flow diagram is a button that, when touched, displays its corresponding configuration
dialog. Some options will be enabled or disabled depending on your SDAIII-CompleteLinQ installation.

The Framework dialog is invoked by choosing Analysis > Serial Data from the menu bar.

Integrated Operation

If you're using Eye Doctor II or VirtualProbe in conjunction with SDAIII-CompleteLinQ, use the Frame­work dialog to configure emphasis, de-embedding/emulation and equalization for the active lane.

Dialog Elements

Enable SDA checkbox - By default checked to enable all views and analyses selected within the SDAIII­CompleteLinQ environment. Unchecking this box will globally disable analysis and turn off all views.

Quick View button - Touch to open the Quick View to configure lane settings.

CAUTION:Using Quick View will clear the current configuration of the selected lane and instead apply the

configuration made within the Quick view window.

Lane 1-4 selector buttons - Touch to activate the lane for configuration. The text displayed beneath each
button in the SDA dialog gives information about the setup for the selected lane.

Ref Lane button - Touch to display the reference lane. This lane stores the data and views from another
lane for comparison purposes (see Store Lane to Ref button below). The name of the stored lane appears
to the right of the button when in use.

NOTE: The Reference Lane is unavailable for use when you enable VirtualProbe capabilities on the De­embed/Emulate dialog.

Lane Enable/Disable checkboxes - Check to enable the corresponding lane for display/analysis. When
multiple lanes are checked, the oscilloscope will enter LaneScape Comparison Mode and display each
lane in its own frame, and the Comparison Mode selection box will be active at the top right of the
screen.

Store Lane to Ref button - Touch to store the setup and data of the active lane to the reference lane.

NOTE:When VirtualProbe is enabled within the De-embed/Emulate dialog, the reference lane is unavail-

able, and the Store Lane to Ref button is disabled.

Copy Lane Setup button - Touch to open a window for copying the setup and data from one lane to
another.

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Signal Input button - Touch to open the Signal dialog, which is used to configure settings for the active
lane including the data source(s), crossing level and signal type, and to enable the display of signal that
"flows"to the Emphasis block of the SDA flowchart.

Emphasis button - Touch to open the Emphasis dialog, which is used to configure pre-emphasis/de­emphasis settings for the signal that flows from the Signal Input(s) block. This button is enabled when
the EyeDoctor II option is present on the oscilloscope. For more information, see Emphasis Overview.

De-embed/Emulate button - Touch to open the De-embed/Emulate dialog, which is used either to con­figure fixture and channel de-embedding/emulation, or to enable the VirtualProbe option for the active
lane. This button is enabled when the EyeDoctor II option is present on the oscilloscope. For more infor­mation, see Emulate / De-embed Overview.

Linear EQ button - Touch to open the Linear EQ dialog, where you can apply CTLE(Continuous Time Lin­ear Equalization) or FFE(Feed-forward Equalization) to the active lane. This button is enabled when the
EyeDoctorII option is present on the oscilloscope. For more information, see Continuous Time Linear

Equalization (CTLE) and FeedForward Equalization (FFE).

DFE button - Touch to open the DFE(Decision Feedback Equalization) configuration window for the
active lane. This button is enabled when the EyeDoctorII option is present on the oscilloscope. For more
information, see Decision Feedback Equalizer (DFE) Configuration.

Clock Recovery Source switch - This unlabeled button is located immediately to the left of the Clock
Recovery button. When using an explicit reference clock, set the Clock Recovery Source switch to the
"Blue"position to enable the Ref Clock Input button.In this position, the clock recovery uses transitions
of the reference clock input. When set to the "Red" position, SDAIII-CompleteLinQ will perform a soft­ware clock recovery using edges from the signal flowing out of the Linear EQ box. In either position, the
settings configured in the Clock dialog are utilized.

Clock Recovery button - Touch to access the Clock dialog.

Ref Clock Input button - When using an explicit reference clock, set the clock recovery switch to the

"Blue" position to enable the Ref Clock Input button. Then, touch Ref Clock Input to open the dialog for
configuring the source and other attributes of the reference clock.

Eye Meas. button - Touch to open the dialog for configuring Eye diagram measurements for the active
lane. For more information, see Eye Measurements Overview.

Jitter Meas. button - Touch to open the dialog for configuring jitter measurements for the active lane.
For more information see Jitter Measurements Overview.

Noise Meas. button - Touch to open the dialog for the configuration of vertical noise measurements. For
more information, see Vertical Noise Measurements Overview. This button is enabled when the Cross-
talk option is present on the oscilloscope.

Crosstalk Meas. button - Touch to open the dialog for configuration of the CrosstalkEye. This button is
enabled when the Crosstalk option is present on the oscilloscope. For more information, see Crosstalk

Analysis.

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LaneScape Comparison Mode

When multiple lanes are enabled for display/analysis, the oscilloscope activates LaneScape Comparison
mode. In this mode, waveforms and views for each lane are placed in separate frames, which you can
arrange into different "LaneScapes" to facilitate analysis. Waveforms and views are synchronized
between LaneScapes.

Selecting a LaneScape Mode

When multiple lanes are enabled, the Comparison Mode selector is displayed at the far right of the appli­cation menu bar.

Touch the icon or text to open the selector to choose a LaneScape mode.

LaneScape Modes

You can choose from three LaneScape modes:

Single - One LaneScape is displayed, allowing maximum screen area for viewing the analysis of a single
lane. If multiple lanes are enabled, tabs for each lane/frame appear above the grid; select the tab for the
frame you wish to display in the LaneScape.

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Dual - Two LaneScapes are shown side-by-side. Tabs for selecting lanes/frames appear above the grid in
both LaneScapes.

Mosaic - All enabled lanes/frames are displayed in their own LaneScapes (up to four).

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Assignment of Traces to LaneScapes

LaneScape mode is architected to facilitate easy comparison of SDAIII-CompleteLinQ results for multiple
lanes. To prevent misinterpretation of results, the waveform for each lane can only be displayed in its
own frame.

Non-SDAIII-CompleteLinQ waveforms, such as input channels, math functions, zooms and memory
traces (C1, F1, Z1, M1, etc.) are not locked to a frame and can be moved from one LaneScape to another.
To move a trace to a different LaneScape, do one of the following:

l Touch the trace to open the context menu, then select "Next LaneScape" to move the trace.

l When using a mouse, right-click on a descriptor box to open the context menu, then select "Next

LaneScape."

l Drag the descriptor box for the trace to the desired LaneScape and grid.

Quick View

The SDAIII-CompleteLinQQuick View shows the eye diagram, TIE track, bathtub curve, jitter histogram,
NQ-scale, and jitter spectrum (with peaks annotated) in a single, summarized view.

SDAII Quick View

You must specify only the input signal for analysis. You can also specify the crossing level.

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Setting Up Quick View

Follow these steps to set up Quick View.

1. If you haven't done so already, touch Analysis → Serial Data on the menu bar or touch the Serial
Data Analyzer button on the Quick Access toolbar.

2. On the SDA Framework dialog, touch the Quick View button. The Signal Input(s) to be Analyzed
pop-up window opens.

3. On the Serial Data Input(s) section, if you are using a differential probe, touch the 1 Input (or Diff.
Probe) button. Now, touch inside the Data field below the 1 Input (or Diff. Probe) button and select
an input source from the Select Source pop-up window.

OR

If you are using two single-ended probes to calculate the differential signal, touch the Input1-Input2
button. Input2 is subtracted from Input1. Touch inside each Data field and select a source for each
Select Source pop-up window.

4. Increase the sampling rate of the signal by touching inside the Upsample by data entry field and
entering the upsample factor . at the bottom of the screen.

5. In the Crossing Level section, if you want to set an absolute crossing level, touch inside the Level is
field and choose Absolute from the pop-up menu. Then, touch inside the Abs Level data entry field
and enter the voltage level at which the signal timing is measured at the bottom of the window.

OR

If you want to use a relative level set to the selected percentage on each acquisition, touch inside the
Level is field and choose Percent from the pop-up menu. Then, touch inside the Percent Level data
entry field and enter the percentage . at the bottom of the window.

Note: You can touch the Find Level button to automatically find the level. The level is found by locat­ing the midpoint between the highest and lowest signal levels in the current acquisition.

6. Click OK to view the summary all on one screen.

Lane Configuration Process

SDAIII-CompleteLinQ offers many alternatives for configuring the analysis on up-to-four lanes, depending
on whether the oscilloscope is equipped with one of the "LinQ" options.

The main SDA Framework dialog is organized like a flowchart and shows some basic setup information
for the active lane, which is made active by touching/clicking one of the Lane selector buttons on the left
half of the dialog.

There are two main configuration approaches:

l Complete the entire configuration for a single lane, then proceed to the next

l Complete the configuration for all lanes at each box in the flow

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The minimum configuration requirement is to:

l Set up a signal

l Set up either a Reference Clock or Clock Recovery

If you have access to Eye Doctor II, you can optionally set up any Emphasis, Emulation/De-embedding of

fixtures, or Equalization you wish to apply to the lane before taking measurements.

You'll also want to set up the Eye, Jitter, Noise, and Crosstalk measurements to be used for analysis.

Return to the SDA Framework dialog at any time by touching/clicking the SDA tab.

Copying Configurations

An efficient approach is to complete the entire configuration for one lane then use the Copy Lane feature
on the SDA Framework dialog to copy that configuration to other lanes. You can then make unique set­tings by activating the desired Lane and touching the appropriate box in the flow to open the cor­responding configuration dialog.

Signal Input vs. Quick View

Signal configuration can be done either via the Signal Input dialog or the pop-up Quick View window.
However, any configurations already made on the Signal Input dialog will be replaced by configurations
made in the Quick View.

Synchronized vs. Independently Configurable Settings

Some settings will be synchronized across all lanes, either for simplicity or to ensure that it is straight­forward to compare results.

l Selections related to the display of results are synchronized across lanes—for example, wave-

forms, histograms, spectra and measurements. Waveforms and other plots for a given lane are
placed in a unique frame. See LaneScape Comparison Mode.

l Several other key settings are synchronized, including:

l Jitter Calculation Method (Jitter Parameters dialog)

l Eye Saturation (Eye Diagram dialog)

l Vertical Eye Scales (Eye dialog)

l Eye Style (Eye Diagram dialog)

l IsoBER start/stop/step (Eye Diagram dialog)

l log10BER (Jitter Parameters dialog)

l Repeating Pattern mode (Pattern Analysis dialog)

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Signal Inputs

Set Up Signal

Follow these steps to define the characteristics of the input signal to be analyzed.

1. On the menu bar, touch Analysis → Serial Data to open the SDA Framework dialog. Then, touch the
Lane # button for the lane you wish to configure.

2. Touch the Signal Inputs button to open the Signal Inputs dialog.

3. In the Serial Data Input(s) section, if you are using a differential probe, touch the 1 Input (or Diff.
Probe) button.

Press the Input1 button and select an input source from the Select Source pop-up window.

OR

If you are using two single-ended probes to calculate the differential signal, touch the Input1-Input2
button. Input2 will be subtracted from Input1. Touch the Input1 and Input2 buttons and select a
source for each from the Select Source pop-up window.

4. If you want to increase the sampling rate of the signal, touch inside the Upsample by data entry field
and enter the upsample factor at the bottom of the screen.

5. In the Crossing Level section, if you want to set an absolute crossing level, touch inside the Level is
field and choose Absolute from the pop-up menu. Then, touch inside the Abs Level data entry field
and enter the voltage level at which the signal timing is measured . at the bottom of the screen.

OR

If you want to use a relative level set to the selected percentage on each acquisition, touch inside the
Level is field and choose Percent from the pop-up menu. Then, touch inside the Percent Level data
entry field and enter the percentage . at the bottom of the screen.

Note: You can touch the Find Level button to automatically find the level. The level is found by locat­ing the midpoint between the highest and lowest signal levels in the current acquisition.

6. Touch the Signal Type field and choose a standard signal type from the list. If you choose Custom
from the list of signal types, enter a bit rate in the Nominal Rate field.

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Signal Dialog

On the SDA Framework dialog, touch the Signal tab or the Signal Inputs button to access the Signal
dialog.

Lane 1-4 buttons at the far left let you select the Lane to be configured for signal. If you made this selec­tion earlier on the SDA Framework dialog, it will persist on the Signal dialog.

Serial Data Input(s) section lets you define the serial data input(s). If you are using a differential probe or
if your signal is connected by one coaxial cable, you can select 1 Input (or Diff. Probe) and specify the
input source in the Input1 box. If you are using two single-ended probes or two coaxial cables, you can
select Input1-Input2 and specify the input sources to use when calculating the differential signal. For
more information, see Serial Data Inputs.

Crossing Level section lets you to set the voltage level at which the signal timing is measured. The cross­ing level is set separately for the data and clock signals (if an external clock is selected) and can either be
an absolute voltage or a percentage of the signal amplitude via the relative selection. You can also con­figure a hysteresis level, and between positive, negative and both edge types for when the "Clock" Signal
Type is selected. The Crossing Level section on this dialog is for the data signal. For more information, see

Crossing Levels.

Signal Type section lets you choose a standard signal type. The signal type you choose automatically
sets the nominal bit rate for the selected standard, and populates the Mask Type selector in the Eye
dialog. For more information, see Signal Types.

Noise Settings includes settings that are used by the vertical noise measurements toolkit. Settings
include the Sample Phase, which determines where in the unit interval the sample is taken for the noise
measurement. Also, see How to Order SDAIII-CompleteLinQ Capabilities for information on which prod-
ucts include the vertical noise analysis capabilities.

NOTE:

l Many of the measurements in SDAIII-CompleteLinQrequire both a high sampling rate and long

memory to compute jitter and vertical noise accurately.

l Lower sampling rates can result in less accurate jitter measurements, and short record lengths can

give incomplete eye patterns or jitter and noise displays that diverge.

l For best results, acquire waveforms with at least 100,000 unit intervals, and of >100 iterations of

the pattern. See Jitter Pattern Analysis.

For step-by-step instructions, see Set Up Signal.

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