Tektronix 80SJNB Online User Manual
OnlineUserManual
80SJNB Advanced Jitter, Noise, and BER
Analysis Software
077 --0011--00
Adapted from the 80SJNB Online
Help Version 076--0022--00
www.tektronix.com
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suppliers, and are protected by national copyright laws and international treaty provisions.
Tektronix products are covered by U.S. and foreign patents, issued and pending. Information in this publication supercedes
that in all previously published material. Specifications and price change privileges reserved.
TEKTRONIX and TEK are registered trademarks of Tektronix, Inc.
Contacting Tektronix
Tektronix, Inc.
14200 SW Karl Braun Drive
P.O. Box 500
Beaverton, OR 97077
USA
For product information, sales, service, and technical support:
H In North America, call 1-800-833-9200.
H Worldwide, visit www.tektronix.com to find contacts in your area.
Table of Contents
Welcome to the Jitter, Noise, and BER Analysis Software iii................
Related Documentation iii...........................................
GPIB Information iii................................................
Relevant Web Sites iv...............................................
Conventions iv....................................................
Types of Online Help Information iv...................................
Using Online Help v...............................................
Feedback vi.......................................................
Getting Started 1............................................
Product Description 1..............................................
Requirements and Restrictions 1......................................
Accessories 1.....................................................
Connecting to a Device Under Test (DUT) 2............................
Deskewing Probes and Channels 2....................................
The Importance of Jitter and Noise Separation 2.........................
Operating Basics 5..........................................
General Information 5..............................................
Navigating the User Interface 9......................................
Setting up the Application for Analysis 15...............................
Saving and Recalling Setup Files 23....................................
Working with Numeric Results 24.....................................
Working with Plots 25...............................................
Parameters 33...............................................
User Settings 33....................................................
Configuration Settings 33............................................
GPIB 35....................................................
Program Example 35................................................
GPIB Commands 35................................................
Variable:Value Command 36..........................................
Measurements Results Queries 39......................................
Error Messages 40..................................................
GPIB Program Example 41...........................................
Application Example 43.......................................
About Application Example 43........................................
Example 44.......................................................
Algorithms 53...............................................
About Measurement Algorithms 53....................................
Test Methodology 53................................................
Correlations 55..............................................
Correlation to Real--Time Oscilloscope Jitter Measurements 55..............
Index 57....................................................
Adapted From the 80SJNB Online Help
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Table of Contents
ii
Adapted From the 80SJNB Online Help
Preface
Welcome to the Jitter, Noise, and BER Analysis Software
The 80SJNB Advanced Jitter, Noise, and BER Analysis Software enhances the
capabilities of the CSA/TDS8000B and CSA/TDS8200 series Tektronix
oscilloscopes. The analysis software includes the following features:
H Advanced jitter and noise analysis
H Separation of jitter and noise
H Perform random and deterministic jitter analysis including BER estimation
H Show results as graphical displays including histograms, spectra, and bathtub
curves
H 2--D eye diagrams that include Correlated Eye, Probability Density Function
(PDF) Eye, and Bit Error Rate (BER) Eye
H Save statistical results to a data file
Related Documentation
GPIB Information
In addition to the online help, you can access other information on how to
operate the oscilloscope and application through the following related documents.
H Relevant Web Sites
H GPIB Information
H Types of Online Help Information
For information on how to operate the oscilloscope and use the application--specific GPIB commands, refer to the following items:
H The online programmers guide for your oscilloscope can provide details on
how to use GPIB commands to control the oscilloscope.
H The programming example.
Adapted From the 80SJNB Online Help
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Preface
Relevant Web Sites
Conventions
The Tektronix web site offers the following information:
H Understanding and Characterizing Jitter Primer, literature number
55W--16146--x.
H Jitter analysis details on the www.tektronix.com/jitter web page.
You can also find useful information in the Fibre Channel -- Methodologies for
Jitter and Signal Quality Specification – MJSQ on the www.t11.org web site.
Online help topics use the following conventions:
H The terms “80SJNB application” or “application” refer to the 80SJNB Jitter,
Noise and BER Analysis software.
H The term “oscilloscope” refers to the product on which this application runs.
H The term “select” is a generic term that applies to the two mechanical
methods of choosing an option: with a mouse or with the Touch Screen.
H The term “DUT” is an abbreviation for Device Under Test.
H User interface screen graphics are from a CSA8200 Communications Signal
Analyzer. There may be minor differences depending on the instrument
model and software versions.
H When steps require a sequence of selections using the application interface,
the “>” delimiter marks each transition between a menu and an option. For
example, one of the steps to recall a setup file would appear as File > Recall
Settings.
Types of Online Help Information
The online help contains the following topics:
H Getting Started topics briefly describes the application and its requirements.
H Operating Basics topics cover basic operating principles of the application.
The sequence of topics reflects the steps you perform to operate the
application.
H Parameters topics cover the User and Configuration default settings.
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Adapted From the 80SJNB Online Help
Using Online Help
Preface
H Application Examples topics demonstrates how to use jitter measurements to
identify a problem with a waveform. This should give you ideas on how to
solve your own measurement problems.
H GPIB Command Syntax topics contain a list of arguments and values that
you can use with the remote commands and their associated parameters.
Online help has many advantages over a printed manual because of advanced
search capabilities. The main (opening) Help screen shows a series of book icons
and three tabs along the top menu, each of which offers a unique mode of
assistance:
H Table of Contents (TOC) tab -- organizes the Help into book--like sections.
Select a book icon to open a section; select any of the topics listed under the
book.
H Index tab -- enables you to scroll a list of alphabetical keywords. Select the
topic of interest to display the corresponding help page.
H Find tab -- allows a text--based search. Follow these steps:
1. Type the word or phrase you want to find in the search box.
2. If the word or phrase is not found, try the Index tab.
3. Select some matching words in the next box to narrow your search.
4. Choose a topic in the lower box, and then select the Display button.
NOTE. The Find tab function does not include words found in graphics.
NOTE. Green--underlined text indicates a hyperlink to another topic. For
example, select the green text to jump to the topic on Feedback to contact
T ektronix.
When you use a mouse, you can tell when the cursor is over an active
hyperlink because the arrow cursor changes to a small pointing hand cursor.
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Preface
Feedback
General Information
Tektronix values your feedback on our products. To help us serve you better,
please send us suggestions, ideas, or other comments you may have about your
application or oscilloscope.
You can email your feedback to techsupport@tektronix.com, FAX at
(503)627--5695, or by phone. Please be as specific as possible and include the
following information:
H Oscilloscope model number, firmware version number, and hardware
options, if any.
H Module and probe configuration. Include model numbers and the channel/
slot location.
H Serial data standard.
Application- Specific
Information
H Signaling rate.
H Your name, company, mailing address, phone number, FAX number.
NOTE. Please indicate if you would like Tektronix to contact you regarding your
suggestion or comments.
H 80SJNB Software version number.
H Description of the problem such that technical support can duplicate the
problem.
H If possible, save the oscilloscope waveform file as a .wfm file.
H If possible, save the oscilloscope and application .stp setup files. Refer to
Saving a Setup File.
Once you have gathered this information, you can contact technical support by
phone or through e--mail. If using e--mail, be sure to enter ”80SJNB Problem” in
the subject line, and attach the .stp and .wfm files.
To include screen shots, from the oscilloscope menu bar, select File >
Export. Waveform… In the Export dialog box, enter a file name with a .bmp
extension and select Save. The file is saved in the C:\My Documents\TDSCSA8000\UI directory.
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Getting Started
Product Description
The 80SJNB software application enhances the capabilities of the CSA/
TDS8000B and CSA/TDS8200 series Tektronix oscilloscopes by providing
Jitter, Noise, and BER analysis.
You can use this application to do the following tasks:
H Jitter and noise analysis from 0.5 Gb/s to greater than 60 Gb/s
H Jitter and noise separation (see the importance of jitter and noise separation)
H Perform random and deterministic jitter analysis including BER estimation
H Show results as graphical displays
H 2--D eye diagrams that include Correlated Eye, Probability Density Function
(PDF) Eye, and Bit Error Rate (BER) Eye
H Save results to a data file
H Save and recall instrument
Requirements and Restrictions
Operating System. This application requires the Microsoft Windows 2000
operating system. Contact Tektronix about purchasing the necessary upgrades for
your instrument.
Memory. This application requires 512 MB of memory (minimum) to perform.
To verify the amount of installed memory, minimize the Tekscope application,
then select Start > Control Panel > System. If less than 512 MB is reported,
contact Tektronix about purchasing the necessary upgrades for your instrument.
Keyboard and Mouse. You will need to use a keyboard to enter new names for
some file save operations. A mouse is not required but simplifies screen
selections.
Accessories
There are no standard accessories for this product. However, you can refer to the
product datasheet available on the Tektronix web site for information on optional
accessories relevant to your application.
setups
Adapted From the 80SJNB Online Help
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Getting Started
Connecting to a Device Under Test (DUT)
You can use any compatible probe or cable interface to connect between your
DUT and the instrument.
WARNING. To avoid electric shock, remove power from the DUT before attaching
probes. Do not touch exposed conductors except with the properly rated probe
tips. Refer to the probe manual for proper use.
Refer to the General Safety Summary in your oscilloscope manual.
Deskewing Probes and Channels
To ensure accurate results for two--channel measurements, it is important to first
deskew the probes or cables and oscilloscope channels before you take measurements.
NOTE. Deskewing is performed from the CSA/TDS8000 series instrument
application, not from the 80SJNB application. Refer to the CSA8000 & TDS8000
User Online Help for information and procedures for deskewing probes and
channels.
The Importance of Jitter and Noise Separation
Jitter is an important characteristic to analyze for serial data links, but the
analysis should not stop at just jitter. To properly evaluate a data link, it is
necessary to analyze both jitter and noise.
Two components need to be added to the traditional jitter analysis:
H The noise/vertical eye closure should be considered in a manner very similar
to that of jitter/horizontal eye closure.
H Jitter measurements based on the threshold crossing of a finite--speed
transition should include vertical noise influence.
Depending on the magnitude of the vertical noise and the transient response of
the transmitter and transmission channel, the magnitude of this influence can
vary widely. Ultimately the jitter and noise analysis allows for accurate BER
projections for the targeted communication link.
Tektronix has written a detailed document explaining the importance of jitter and
noise separation.
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Adapted From the 80SJNB Online Help
Go to the Tektronix Web site:
www.tektronix.com
At the Tektronix home page, select oscilloscopes > sampling
You can download a pdf of the white paper titled:
Tektronix CSA/TDS8200 Jitter Analysis Application: Jitter and Noise
Analysis, BER Estimation Descriptions
Getting Started
Adapted From the 80SJNB Online Help
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Getting Started
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Adapted From the 80SJNB Online Help
Operating Basics
General Information
The Operating Basics book covers the following tasks:
H Navigating the user interface
H User interface information
H Using oscilloscope functions
H Setting up the application
H Viewing the measurement results as plots
H Exporting Plot Files
H Saving and recalling setup files
Starting the 80SJNB
Application
Returningtothe
Oscilloscope Application
There are several ways to start the 80SJNB application.
H If the TDS/CSA8000 Series application is minimized, you can start the
80SJNB application by selecting the shortcut located on the Windows
desktop area.
H If the TDSCSA8000 Series oscilloscope application is running and open,
you can use the Applications menu on the menu bar and select the 80SJNB
application.
H Use the Windows Start menu by selecting Start > Programs > Tektronix
TDSCSA8000 > 80SJNB > 80SJNB.
The 80SJNB application fills the entire screen and hides the oscilloscope
application. To return to the oscilloscope display, press the Back to Scope button
in the toolbar.
You can also minimize the 80SJNB application or exit the 80SJNB application
entirely.
Adapted From the 80SJNB Online Help
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Operating Basics
Returning to the 80SJNB
Application
The CSA/TDS8000 oscilloscope application fills the entire screen. If the
80SJNB application is already running but the oscilloscope application is
displayed on top, bring the 80SJNB application to the front using the following
methods.
H Press the App button on the oscilloscope toolbar.
H Select Switch to 80SJNB from the Applications pull--down file menu.
If you have a keyboard attached, you can switch between running
applications by pressing the Alt + Tab keys.
Minimizing and
Maximizing the
Application
Exiting the Application
Directory Structure for the
80SJNB Application
To minimize the application to the Windows task bar, select the
button in the application menu bar.
To maximize the application, select the minimized application from the
Windows task bar. Alternately, if you have a keyboard attached, you can switch
between displayed applications by pressing Alt + Tab keys.
To exit the application, select File > Exit or the
application menu bar.
Installation Directory
The 80SJNB software is installed in the following directory:
C:\Program Files\TekApplications\80SJNB
Save and Recall Directory
The directory structure used for saving and recalling setup files and exporting
data depends on how the Windows operating system is configured for networking and login purposes.
command button in the
command
H If users are required to log in, the save, recall, and export default location is:
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Adapted From the 80SJNB Online Help
File Name Extensions
Operating Basics
C:\Documents and Settings\username\My Documents.
H If no login requirements are set, the default location is:
C:\My Documents.
Extension Description
.bmp File that uses a bitmap format
.csv File that uses a comma separated value format
.stp 80SJNB application setup file
.jpg File that uses a joint photographic experts group format
.mat File that uses native MATLAB binary format
.png File that uses a portable network graphics format
.txt File that uses an ASCII format
File Menus
Tips on the 80SJNB User
Interface
You can use the File menus to save and recall different application setups and
recently accessed files.
CAUTION. Do not edit a setup file or recall a file not generated by the application.
Menu/function Description or function
Save Settings Saves the current application settings in a .stp file
Recall Settings Browse to select an application setup (.stp) file to recall; restores the application and
Export Waveform Exports the underlying waveform correlated pattern data used for processing
Print Prints the displayed plots and the detailed statistics list
Print to File Creates a .prn file of the displayed plots and a detailed statistics list
Exit Exits the application
oscilloscope to the values saved in the setup file
Here are some tips to help you with the application user interface.
The toolbar provides you with most of the functions you need to configure the
settings, start the acquisition, and control the numerical and plot displays.
H The Configure button
displays a dialog box to configure the target
source for measurement and controlling the most relevant oscilloscope
setups.
H Pressing the Run button
plot displays, and then starts the acquisition and processing cycle.
Adapted From the 80SJNB Online Help
first clears all current measurement data and
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Operating Basics
Oscilloscope Settings
H The Free Run button toggles between blue
sequence) and orange
H Use the plot selection button in the plot displays to access the drop--
down menu for tasks to perform for that plot window, such as assigning a
new type of plot display.
You should return the oscilloscope to its default state before launching the
80SJNB Configuration dialog box. All other acquisitions and math waveforms
should be off, as well as all measurements, waveform databases, masks, and
histograms. You should not have to make changes to the oscilloscope settings via
the oscilloscope UI to successfully acquire data with the 80SJNB application.
The most relevant oscilloscope settings are accessible using the Configuration
dialog box of the 80SJNB application.
Some test setups require oscilloscope settings (such as wavelength and external
attenuation). Make changes to the oscilloscope settings before running the
analysis.
NOTE. Changing oscilloscope settings while the 80SJNB application is acquiring
data may cause errors, unpredictable results, or failure.
for Free Run On.
for Free Run Off (single
About the Results
Clearing Results
To bring the CSA/TDS application to the front of the display, press the Back to
Scope button
use the Alt + Tab keys to switch between applications if you have a keyboard
attached.
There are two ways to view analysis results: as numeric data and as graphical
plots.
You can log the results data to .csv files for viewing in a spreadsheet, database,
text editor or data analysis program.
Press the Clear Data
You may want to clear the data before acquiring new data or between cycles
when the Sequence mode is set to free--run.
NOTE. The numeric results and plot files are erased each time a new acquisition
cycle is started by the user.
or minimize the 80SJNB application. Alternately, you can
button to remove the existing plot displays and results.
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Adapted From the 80SJNB Online Help
Operating Basics
About Plotting
The application displays the results as 2--dimensional plots for more comprehensive analysis. Before or after you take measurements, you can select to display a
single plot, two plots or four plots. You can select the type of data you want to
view in each plot window.
Navigating the User Interface
Windows User Interface
About the User Interface
The application uses a Microsoft Windows--based user interface.
NOTE. The oscilloscope application is hidden when the 80SJNB application is
running and not minimized.
Adapted From the 80SJNB Online Help
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Operating Basics
User Interface Items Definitions
Item Description
Area Visual frame that encloses a set of related options
Box Use to define an option; enter a value with the Keypad or a Multipur-
pose knob
Browse Displays a window where you can look through a list of directories and
files
Check box Use to select or clear an option
Command button Initiates an immediate action, such as the Start command button in the
Control panel
Keypad On--screen keypad that you can use to enter numeric values
Menu All options in the application window (except the Control panel) that
display when you select a menu bar item
Menu bar Located along the top of the application display and contains
application menus
Status bar Line located at the bottom of the application display that shows the
acquisition status and the latest Warning or Error message
Virtual keyboard On--screen keyboard that you can use to enter alphanumeric strings,
such as for file names
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Adapted From the 80SJNB Online Help
80SJNB User Interface
Information
Operating Basics
Item Description
Scroll bar Vertical or horizontal bar at the side or bottom of a display area that
you use to move around in that area
Tool bar Located along the top of the application display and contains
application quick launch buttons
About Navigation
The application provides you with several means to display the results:
H The drop--down menus available in the menu bar allows for screen configu-
ration (one, two, or four plots, summary or full numeric results table)
H The buttons in the tool bar allow for screen configuration
H The drop--down menus available in the plot display windows allow you to
choose from the available plots, as well as Copy, Examine, and Export plots
H The status bar at the bottom of the screen contains progress information and
displays error conditions detected
H Double clicking on a displayed graph opens the plot in a Matlab window.
Matlab provides additional display capabilities such as panning, zooming,
data cursors, and 3D rotation. The Examine… button from the drop--down
menu of the plot also opens the Matlab window.
Adapted From the 80SJNB Online Help
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Operating Basics
About the 80SJNB Tool Bar
The toolbar provides you with most of the functions you need to configure the
settings, start the acquisition, and control the numerical and plot displays. Most
tasks are also available using the drop--down lists from the File menu bar.
H Configure button . Use the Configure button to display the Configura-
tion dialog box, allowing you to select and configure the source for
measurements and control key oscilloscope setups. The Configuration button
is disabled during the acquisition and processing cycle.
H Free Run on/off button . Use the Free Run button to select the sequence
mode (free run on or off).
When OFF, the button remains blue and the acquisition and processing cycle
completes one pass over the entire pattern. Off is the default mode.
When Free Run is ON, the button turns orange
acquisition and processing cycle will repeat until stopped by the user. The
indicating that the
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Adapted From the 80SJNB Online Help
Operating Basics
correlated components are averaged with previous data while the uncorrelated components are accumulated for increased statistical content. At the
completion of each acquisition cycle, the plots and measurements are
updated.
If you want to halt a Free Run cleanly, select the
button. This converts
the Free Run mode to Single Sequence mode, so that the acquisition stops
when the cycle is complete.
H Run button
. Use the Run button to start the acquisition and processing
cycle. Once the run button is pressed, do not change any instrument settings.
When the Run button is pressed, all current measurement data and plot
displays are cleared. During the acquisition and processing cycle the
Configuration and Run buttons are disabled.
H Pause button
. Use the Pause button to interrupt the current acquisition
and processing cycle. Press the button again to resume the cycle. This can be
useful when the acquisition is set to Free Run, allowing you to halt the
acquisition and processing cycle so you can view and save the measurement
data between cycles.
H Stop button
. Use the Stop button to end the acquisition and processing
cycle. While in Single Sequence mode, stopping the cycle produces no
results and you must press the Start button to start a new cycle.
H Clear Data button
. Use the Clear Data button to clear all results and plot
displays. If Free Run is set to ON (cumulating previous data with new), you
can clear the existing results and plots during the processing cycle, thus
starting a new acquisition and processing cycle.
H Plot Display . Use the window pane buttons to display between
1, 2, or 4 plots. The number of plot displays can be changed at any time.
H Numeric Results Display
complete list of statistics with no plots displayed.
H Return to Scope
oscilloscope display to the front of the screen.
Adapted From the 80SJNB Online Help
. The results button changes the display to a
. Use this button to bring the CSA/TDS 8000
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