Tektronix 071-0590-00 User Manual
pp
User Manual
gigaBERT1400
1400 Mb/s Bit Error Rate Tester
Generator and Analyzer
071-0590-00
This document supports firmware version 2.2 and above.
Copyright © 2000 Tektronix, Inc. All rights reserved. Licensed software
products are owned by Tektronix or its suppliers and are protected by United
States copyright laws and international treaty provisions.
Use, duplication, or disclosure by the Government is subject to restrictions as set
forth in subparagraph (c)(1)(ii) of the Rights in Technical Data and Computer
Software clause at DFARS 252.227-7013, or subparagraphs (c)(1) and (2) of the
Commercial Computer Software - Restricted Rights clause at FAR 52.227-19, as
applicable.
Tektronix products are covered by U.S. and foreign patents, issued and pending.
Information in this publication supersedes that in all previously published
material. Specifications and price change privileges reserved.
Tektronix, Inc., P.O. Box 1000, Wilsonville, OR 97070-1000
TEKTRONIX and TEK are registered trademarks of Tektronix, Inc.
GB1400 User Manualii
WARRANTY
Tektronix warrants that this product will be free from defects in materials and workmanship for a
period of one (1) year from the date of shipment. If any such product proves defective during this
warranty period, Tektronix, at its option, either will repair the defective product without charge
for parts and labor, or will provide a replacement in exchange for the defective product.
In order to obtain service under this warranty, Customer must notify Tektronix of the defect
before the expiration of the warranty period and make suitable arrangements for the performance
of service. Customer shall be responsible for packaging and shipping the defective product to the
service center designated by Tektronix, with shipping charges prepaid. Tektronix shall pay for
the return of the product to Customer if the shipment is to a location within the country in which
Tektronix service center is located. Customer shall be responsible for paying all shipping charges,
duties, taxes, and any other charges for products returned to any other locations.
This warranty shall not apply to any defect, failure or damage caused by improper use or
improper or inadequate maintenance and care. Tektronix shall not be obligated to furnish service
under warranty a) to repair damage resulting from attempts by personnel other than Tektronix
representatives to install, repair or service the product; b) to repair damage resulting from
improper user or connection to incompatible equipment; or c) to service a product that has been
modified or integrated with other products when the effect of such modification or integration
increases the time or difficulty of servicing the product.
THIS WARRANTY IS GIVEN BY TEKTRONIX WITH RESPECT TO THIS PRODUCT
IN LIEU OF ANY OTHER WARRANTIES, EXPRESSED OR IMPLIED. TEKTRONIX
AND ITS VENDORS DISCLAIM ANY IMPLIED WARRANTIES OF
MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. TEKTRONIX’
RESPONSIBILITY TO REPAIR OR REPLACE DEFECTIVE PRODUCTS IS THE
SOLE AND EXCLUSIVE REMEDY PROVIDED TO THE CUSTOMER FOR BREACH
OF THIS WARRANTY. TEKTRONIX AND ITS VENDORS WILL NOT BE LIABLE
FOR ANY INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
IRRESPECTIVE OF WHETHER TEKTRONIX OR THE VENDOR HAS ADVANCE
NOTICE OF THE POSSIBILITY OF SUCH DAMAGES.
GB1400 User Manual iii
iv
How to Reach Customer Service
If you have any questions regarding the operation, maintenance, repair,
or application of your Tektronix equipment, contact your local sales
and service office. For a complete list of the Worldwide Sales and
Service Offices contact (800) 426-2200.
Tektronix provides high quality Technical Support on applications,
operation, measurement specifications, hardware, and software by
expert application engineers. For Applications Support, call the
Customer Support Center listed below.
Mailing
Address
Tektronix, Inc.
Measurement Business Division
P.O. Box 500
Beaverton, Oregon 97077-0001
USA
Customer
and Sales
Support
800-TEK-WIDE
or
800-835-9433 Ext 2400
Center
Direct
Fax
503-627-2400
503-627-5695
E-Mail tm_app_supp@tek.com
Web Site http://www.tek.com
Attn. Customer Service
Hours are 6:00 AM to 5:00 PM,
Pacific Time.
After hours Voice Mail is available.
GB1400 User Manual
Table of Contents
Safety.................................................................................................. xii
Getting Started
Features............................................................................................... 1-1
Ordering Information ............................................................................ 1-4
gigaBERT comparison chart.................................................................. 1-5
Initial Self-Check Procedure ................................................................. 1-7
Operating Basics
Functional Overview....................................................................................... 2-1
BERT Basics - GB1400 ........................................................................ 2-2
Controls, Indicators, and Connectors...................................................... 2-4
Display Formats ................................................................................... 2-6
Outputs & Inputs.................................................................................. 2-9
Generator OUTPUT ....................................................................... 2-9
Generator CLOCK ......................................................................... 2-10
Generator OUTPUT (Set-up) ........................................................... 2-11
Generator Rear Panel...................................................................... 2-12
Changing the Line Fuse .................................................................. 2-12
Analyzer INPUT............................................................................ 2-13
Analyzer MONITOR ...................................................................... 2-14
Analyzer Rear Panel....................................................................... 2-15
Changing the Line Fuse .................................................................. 2-15
Connectors, Terminations and Levels .............................................. 2-16
Controls & Indicators............................................................................ 2-18
Power Switches .............................................................................. 2-18
Unit Mounting ............................................................................... 2-18
Unit Cooling .................................................................................. 2-18
View Angle and Panel Lock Keys ................................................... 2-18
Reset to Factory Default.................................................................. 2-18
GPIB Controls................................................................................ 2-19
Pattern Controls and Function Keys ................................................. 2-20
Function (Soft) Keys (F1, F2, F3, F4) ............................................... 2-21
GB1400 User Manual v
Table of Contents
Generator ERROR INJECT ............................................................ 2-22
Analyzer INPUT............................................................................ 2-23
Analyzer Error History.................................................................... 2-24
Analyzer ERROR DETECTION ..................................................... 2-25
Analyzer SYNC Controls ................................................................ 2-25
Burst Mode Option ............................................................................... 2-26
Burst Mode Usage.......................................................................... 2-27
Specifications for Burst Mode ......................................................... 2-27
PECL Option for GB1400 Tx ................................................................ 2-29
Tutorial........................................................................................................... 2-30
Applications .................................................................................................... 2-38
Method for Very Fast Automatic RX Synchronization
and Eye Width Measurement ......................................................... 2-38
GB700/ GB1400 Optical Component Test........................................ 2-46
Reference
Menu Overview.................................................................................... 3-1
Functions common to TX and RX.......................................................... 3-1
Selecting a Pattern................................................................................ 3-2
Fibre Channel Link Testing Parallel and High-Speed Serial............... 2-47
Testing QPSK Modems, I & Q ........................................................ 2-48
QPSK BER Testing using PRBS Data for 2-Channel I & Q ............... 2-49
AC Power...................................................................................... 3-1
Selecting 115 VAC or 230 VAC operation ....................................... 3-1
Turning Instrument Power ON/OFF................................................. 3-1
LCD Viewing Angle ....................................................................... 3-1
Recalling Default Setup................................................................... 3-2
Locking the Front Panel.................................................................. 3-2
Pattern Definitions.......................................................................... 3-2
PRBS Patterns ............................................................................... 3-2
Word Patterns ................................................................................ 3-3
Selecting an Active Pattern................................................................... 3-3
Selecting PRBS Patterns ................................................................. 3-3
Selecting the Current Word Pattern.................................................. 3-3
Selecting (Recalling) a Saved Word Pattern..................................... 3-4
GB1400 User Manualvi
Table of Contents
Word Patterns ...................................................................................... 3-5
Basics............................................................................................ 3-5
Creating Word Patterns using front panel controls ............................. 3-5
Creating Word Patterns using menus................................................ 3-7
Creating Word Patterns using remote control.................................... 3-8
Saving Word Patterns ..................................................................... 3-9
Recalling Word Patterns ................................................................. 3-9
Generator Functions ....................................................................................... 3-10
Clock Source and Frequency................................................................. 3-10
External Clock Input............................................................................. 3-10
Clock Source........................................................................................ 3-10
Step Size and Frequency ....................................................................... 3-10
Saving a Frequency.............................................................................. 3-11
Recalling a Frequency........................................................................... 3-11
Data and Clock Outputs ........................................................................ 3-12
Amplitude and Baseline Offset.............................................................. 3-14
Logically Inverting Output Data (D-INV) .............................................. 3-15
Single-Ended or Differential Operation ................................................. 3-16
Pattern SYNC (PYNC) and CLOCK/4 Outputs ...................................... 3-16
Error Injection ...................................................................................... 3-17
Selection an Error Inject Mode .............................................................. 3-17
Error INJECT Input.............................................................................. 3-18
Analyzer Functions ......................................................................................... 3-19
Automatic Setup Functions (SYNC)...................................................... 3-19
AUTO SEARCH with PRBS Patterns.................................................... 3-20
AUTO SEARCH with "Non-PRBS" Patterns ......................................... 3-21
How to DISABLE Automatic Pattern Resynchonization.......................... 3-21
Relationship between AUTO SEARCH and DISABLE........................... 3-21
Synchronization (LOCK) Threshold ....................................................... 3-22
Clock, Data, and Reference Data Inputs................................................. 3-23
Input Data Delay.................................................................................. 3-24
Input Termination................................................................................. 3-25
Input Decision Threshold ...................................................................... 3-26
Logically Inverting Input Data ............................................................... 3-26
GB1400 User Manual vii
Table of Contents
Single-Ended or Differential Operation .................................................. 3-27
Selecting the Reference Data Mode ....................................................... 3-27
Monitor Outputs................................................................................... 3-28
Error Detection Set-up .......................................................................... 3-29
Display Mode: Totalize, Window or Test ............................................... 3-33
Clearing Results and Starting Tests ........................................................ 3-33
Totalize Process Setup.......................................................................... 3-33
Window Process Setup.......................................................................... 3-34
Test Process Setup................................................................................ 3-35
Viewing Results ................................................................................... 3-36
Printing Results (Reports) ..................................................................... 3-37
Result Definitions ................................................................................. 3-42
Error History Indicators ........................................................................ 3-44
CLEAR Control.................................................................................... 3-45
Audio (Beeper) Function....................................................................... 3-45
Analyzer Error Messages...................................................................... 3-45
Starting & Stopping Measurements........................................................ 3-46
Menus ............................................................................................................. 3-48
Functions Performed using the Menu System......................................... 3-48
Menu and Function "Pages".................................................................. 3-48
General Rules for using the Menu System .............................................. 3-51
Menu Summaries.................................................................................. 3-52
Menu Function Definitions.................................................................... 3-55
Word Edit (EDIT) .......................................................................... 3-56
Word Length (LENGTH) ................................................................ 3-57
Word Fill (FILL) ............................................................................ 3-58
Word Order (ORDER).................................................................... 3-59
Word Synchronization Threshold (SYNC) ....................................... 3-60
Buffer............................................................................................ 3-61
Auto .............................................................................................. 3-62
Test Length (LENGTH) .................................................................. 3-63
Test Mode (MODE) ....................................................................... 3-64
Test Reports (REPORT) ................................................................. 3-65
Test Threshold (THRES)................................................................. 3-66
Test Squelch (SQUEL)................................................................... 3-67
GB1400 User Manualviii
Table of Contents
Test Print (PRINT)......................................................................... 3-68
Test View Previous (VIEW-PRE).................................................... 3-69
Test View Current (VIEW-CUR) .................................................... 3-70
Window Mode (MODE)................................................................. 3-71
Window Interval in Bits (BITS)....................................................... 3-72
Window Interval in Hrs:Min:Sec (SECOND)................................... 3-73
Window Reports (REPORT) ........................................................... 3-74
RS-232 Baud Rate (BAUD)............................................................ 3-75
RS-232 Parity (PARITY) ................................................................ 3-76
RS-232 Data Bits (SIZE) ................................................................ 3-77
RS-232 End-of-Line Char.(EOL)..................................................... 3-78
RS-232 Xon/Xoff (XON/XOFF)...................................................... 3-79
RS-232 Echo (ECHO) .................................................................... 3-80
GPIB............................................................................................. 3-81
Utility Option (OPTION) ................................................................ 3-82
Utility Version (VER) ..................................................................... 3-83
Time Option (DATE)...................................................................... 3-84
Time Option (TIME)....................................................................... 3-85
Appendices
Specifications .................................................................................................. A-1
BERT Primer/ Technical Articles ................................................................... B-1
Remote Commands ......................................................................................... C-1
Using GPIB, RS-232 ....................................................................................... D-1
Customer Acceptance Test ............................................................................. E-1
Default Settings .............................................................................................. F-1
Cleaning Instructions ..................................................................................... G-1
Pattern Editing Software ................................................................................ H-1
Theory of Operation ....................................................................................... I-1
Glossary.......................................................................................................... Glossary-1
Index .............................................................................................................. Index-1
GB1400 User Manual ix
Table of Contents
List of Figures
2-1 Example of BERT Application........................................................ 2-2
2-2 Nominal Generator NRZ Data and Clock Output Waveforms ........... 2-3
2-3 & 2- 4 Generator (TX) Front & Rear Panels ..................................... 2-4
2-5 & 2-6 Analyzer (RX) Front & Rear Panels ....................................... 2-5
2-7 Generator Display .......................................................................... 2-6
2-8 Analyzer Display........................................................................... 2-7
2-9 Transmitter Burst Mode Operation.................................................. 2-28
2-10 Receiver Burst Mode Operation .................................................... 2-28
3-1 Nominal Generator Clock, Data Waveforms showing Amplitude,
Baseline Offset and Vtop................................................................ 3-13
3-2 Generator Clock and Data Output Equivalent Circuits...................... 3-17
3-3 Analyzer Clock and Data Input Equivalent Circuits .......................... 3-22
3-4 TOTALIZE Measurement Process.................................................. 3-30
3-5 WINDOW Measurements Process.................................................. 3-31
3-6 TEST Measurement Process........................................................... 3-32
B-1 Three-stage PRBS generator .......................................................... B-5
B-2 Four-stage PRBS generator............................................................ B-5
B-3 Seven-stage PRBS generator.......................................................... B-6
I-1 Block Diagram - GB1400 TX.......................................................... I-5
I-2 Block Diagram - GB1400 RX.......................................................... I-6
GB1400 User Manualx
List of Tables
2-1 Generator Inputs & Outputs............................................................ 2-16
2-2 Analyzer Inputs & Outputs............................................................. 2-17
3-1 PRBS (2N-1) Test Patterns............................................................. 3-3
3-2 Output Setup Rules vs. Termination Impedance ............................... 3-14
3-3 Data Inhibit Logic .......................................................................... 3-18
3-4 Actions taken by Analyzer when Synchronization is Lost................. 3-20
3-5 Synchronization Threshold ............................................................. 3-22
3-6 How F2, F3 determine Input Set-up ................................................ 3-24
3-7 Input Terminations for CLOCK, DATA, and REF DATA ................ 3-25
3-8 Input Threshold Range as a Function of Termination ........................ 3-26
3-9 How to Tell which Display Mode is Active ...................................... 3-37
3-10 Menu Descriptions ....................................................................... 3-52
Table of Contents
3-11 Analyzer Menu System Overview ................................................. 3-53
3-12 Generator Menu System Overview................................................ 3-54
B-1 PRBS Polynomials and Shift Register feedback taps for PB200........ B-4
B-2 PRBS Polynomials, Shift Register feedback taps, GB700/ GB1400 .. B-4
GB1400 User Manual xi
Safety
Safety Terms Used in This User's Guide
CAUTION!
WARNING! Indicates an operation or practice that could result in
Indicates an operation or practice that could harm the
instrument.
personal injury or loss of life.
Safety Labels Found on the Instrument
DANGER
High Voltage
Protective Ground
(Earth) Terminal
ATTENTION
Refer to Manual
AC Power
The instrument is designed to operate from a power source that provides no more
than 250 volts RMS between the two supply conductors or between either supply
conductor and ground.
Ground the Instrument
The GB1400 is grounded through its AC power cord. Plug this power cord only
into a properly grounded, three-conductor outlet. If you operate the instrument
without a proper ground then all metal surfaces on the instrument become
potential shock hazards.
To avoid potential hazards, use this product only as specified.
Use the Proper Fuse
Operating the instrument with an improper fuse creates a fire hazard. The correct
fuses to install in the GB1400 are shown below:
Power Voltage Fuse Type
115 VAC 5A, Slo-Blo
230 VAC 5A, Slo-Blo
Do Not Operate in Explosive Atmospheres
This instrument does not provide protection from static discharges or arcing
components and therefore must not be operated in an explosive atmosphere.
xii GB1400 User Manual
Table of Contents
Do Not Remove Instrument Covers
To avoid a shock hazard and to maintain proper air flow, never operate the
GB1400 with any of its outside covers removed.
Static Sensitive Device Notice
GB1400 outputs use a GaAs FET design and therefore are susceptible to damage
from externally applied over-voltage or electrostatic discharge. Never apply
reverse voltage to DATA or CLOCK outputs or voltages that are outside the
range specified in Appendix A of this manual. Operate the instrument only in a
static-controlled environment.
SMA Connectors
Be careful when attaching test cables to SMA connectors. Always tighten the nut
on the SMA connector rather than the cable itself. Never tighten an SMA
connector nut using more than 10 lb.-in. of torque.
Behavior of Outputs - Turning Power On or Off
When the GB1400 Generator is powered or de-powered its DATA and CLOCK
outputs may saturate to their specified positive or negative rail, that is +2 V or - 2
V, for up to 400 milliseconds. If this condition could be harmful to your
equipment, then remove all connections to your GB1400 Generator CLOCK and
DATA outputs before powering or de-powering the instrument.
Unit Mounting
The GB1400 is designed to be placed: (1) flat on a level surface, capable of
supporting its weight, or (2) angled from the surface with the rotating carrying
handle. To change the handle's orientation, press both handle-locking buttons
(located at the hubs of the handle), rotate the handle to the desired angle, and
release the buttons. The handle will click into a locked position. Assure that the
handle is locked before placing the unit on a work surface. A Rack mounting
option is available for installation of the unit into a 19" rackmount. The rack
height for the GB1400 is 7 inches (four RMU).
Unit Cooling
The rear panel fan openings and top-mounted ventilation slots must be kept clear
for proper cooling of the unit. Allow a minimum of two (2) inches of rear panel
clearance, and one (1) inch of top clearance, while operating the unit.
GB1400 User Manual xiii
Preface
This manual describes how to use the Tektronix GB1400 Test Set. The product is
also known by the name, gigaBERT1400. This manual is your primary source of
information on how to use the GB1400 functions.
How This Manual is Organized
This manual is divided into four sections: Getting Started, Operating Basics,
Reference, and Appendices.
Getting Started provides an overview of the GB1400 and describes first time
operation.
Operating Basics describes the hardware controls, indicators, connectors, and
display elements for Tx, Rx and the cabling required. There is also a tutorial and
an application note in this section.
Reference describes the LCD Menus and Screens.
The Appendices provide a listing of specifications, a BERT technology primer,
Theory of Operation, Remote Commands, default factory settings, an extensive
Customer Acceptance Test and other useful information.
Conventions
This manual uses the following conventions:
• The names of front-panel controls and menus appear in all upper case letters,
for example, TRANSMIT and HELP.
• Names appear in the same case in this manual as they appear on the display
screens of the GB1400.
• Within a procedure, a specific button to be pressed or a parameter to be
selected appears in boldface print.
Some procedures require several iterations of highlighting parameters and
selecting choices. Some procedures may require more than one menu button or
menu page selection as well.
xiv GB1400 User Manual
Related Manuals
The following document is also complementary to the GB1400:
• The GB700 BER Tester User Manual (Tektronix part number
Preface
070-9393-02) describes how to operate the GB700 test set.
GB1400 User Manual xv
Preface
GB1400 User Manualxvi
Getting Started
Getting Started
GB1400 Pattern Generator and Error Detector
Features
• Test digital data transmission up to 1400 Mb/s
• Set Data Rate with 1 kHz resolution
• Vary Clock and Data timing with 5 pS
resolution
• Phase-Synchronous Clock and Data Edge
Tracking
• 1-Mbit data pattern memory
• Measure Eye-Width at Specific BER
Automatically
• Auto-Synchronization Rx/Tx Lock-up
• Front panel or computer control operation
The GB1400 is a general-purpose 1400 Mb/s bit error rate tester (BERT) built to
meet the exacting standards of design engineers who need to verify and
characterize high-speed serial data transmission circuits, interfaces and systems.
While primarily a lab instrument, the GB1400’s compact design, full computer
programmability and relatively light weight also enable it to serve in
manufacturing ATE and field test applications.
The quality of a digital link depends on many factors, but everything comes
down to the issue of whether the circuit exhibits a satisfactory BER (bit error
rate) and has sufficient margin to function under stress conditions.
The GB1400 has all of the features you expect in a general-purpose BERT, and
some you expect only in more expensive instruments, such as automated eyewidth measurements at a specified BER, and the ability to accept an external
real-time data stream for bit error testing. Also, the GB1400 has options to add
advanced features, such as Burst Mode (which also extends external clock range
down to 150 kb/s), and a 1-Mbit programmable pattern memory option.
GB1400 User Manual 1-1
Getting Started
Symmetrical, Low-Jitter Output Waveforms
The GB1400 generates low-jitter, symmetrical waveforms over its entire
operating frequency range. The clock and data ports provide both true and
inverted output signals. The instrument can drive single-ended or differential
ECL inputs.
Applications
The GB1400 is focused on the research, design, and manufacturing of
telecommunication components, modules, or links operating at data rates to
1400 Mb/s. It is frequently employed in testing and development well under this
top speed rating, where sharp clock and data waveforms are especially desired, or
where additional frequency range is thought to be needed in the future.
Sample Applications
• Development of Gigabit LAN/Data Comm Devices:
• High-Speed Fibre Channel, Ethernet
• Digital Video (MPEG, SDV, HDDV)
• Wideband Satellite Data Links
• SONET/SDH Network Devices up to OC-12e/STM4e
• High-speed GaAs/ECL/E/O device testing
• Test Clock Recovery Circuits
• Parallel-to-Serial Analysis with Tektronix MB100
• Testing of High Speed Fibre Channel links up to 1,063 Mb/s
• Gigabit Ethernet at 1,250 Mb/s.
• Testing of high-speed Optical Busses (Opto Bus, Opto Bahn) at 800 Mb/s per
channel.
• Satellite system testing and TDMA (Burst Mode) at 400, 800 Mb/s
• GaAs, ECL and optical component testing
PRBS Or User-Defined Test Patterns
The GB1400 can generate pseudo-random bit sequences (PRBS) up to 223−1 bits
and others up to 1-Mbit in length, via user-programmable patterns. Patterns can
be created locally using setup menus or externally by using a workstation or PC.
A PC Windows-based MLPE Pattern Editor software package comes with the
1-Mbit Memory Option. Externally created patterns can be downloaded via the
GPIB or RS-232 port. All user patterns are saved in battery-backed RAM.
1-2 GB1400 User Manual
Getting Started
Adjustable Inputs For Maximum Flexibility
The clock and data ports on the GB1400 Error Detector accept both true and
inverted inputs. Single-ended or differential signals can be internally terminated.
Input data delay is adjustable over a 4 ns range to accommodate different clock
and data signal path delays.
Auto Search For Easy Setup
Auto search greatly simplifies the Error Detector setup. The GB1400 Error
Detector automatically synchronizes to the incoming signal by 1) Setting the
input data decision voltage to its optimum value; 2) Adjusting input data delay
for an optimum clock/data phase relationship; 3) Selecting the correct PRBS test
pattern; and 4) selecting the correct pattern polarity (normal or inverted).
It synchronizes with any pattern sourced by a gigaBERT Pattern Generator. It
can perform a bit-by-bit comparison of an external data stream via the Reference
Data input. Thus the GB1400 can perform bit error analysis on any data pattern
with a known good reference pattern.
Powerful Analysis And Reporting Functions
The GB1400 performs a full-rate, bit-by-bit analysis of the received signal. Bit
error results are then used to calculate three bit error rate (BER) measures. Total
BER is calculated from the last power-on or reset. Window BER is calculated
over a sliding window specified in terms of time (1 second to 24 hours) or bits
(18- to 116-bits). Test BER is calculated from the start of the current test. A hard
copy of all test results can be generated locally by connecting a printer to the
parallel printer port or GPIB or RS-232 port. Reports may be printed when an
error is detected, at the end of test intervals, or both.
Front Panel Or Automated Operation
The GB1400 provides easy operation augmented by set-up store and recall.
Clear, concise LCD displays of setup and results make it easy to use. The 1
Megabit memory option for both the Pattern Generator and the Error Detector is
sufficient for storing and outputting complex data such as SONET frames, ATM
cells, MPEG digital video, etc, allowing designers to simulate “live” traffic. The
GB1400 Pattern Generator and Error Detector can be controlled via the GPIB or
RS-232 interface ports. The gigaBERT remote command set includes commands
for all setup menus and front panel selections. The status of front panel indicators
and test results can be remotely accessed.
Burst Mode
BURST mode, allows for operation with non-continuous external clocks. Use of
BURST mode requires ECL-level signals with a minimum rate during the burst
of 150 kHz. This is an option to the GB1400. See a write-up on Burst Mode at
the end of the Functional Overview section of Chapter 2.
GB1400 User Manual 1-3
Getting Started
Ordering Information
gigaBERT GB1400
1400 Mb/s BERT Generator and Detector. Not available in Europe.
Includes: Power Cord, Manual.
Opt. 02 - 75 Ohm Both Sets.
Opt. 05 - BURST Mode Both Sets.
Opt. 07 - Positive ECL (Pattern Generator Only).
Opt. 08 - 1-Mbit RAM WORD Both Sets & PC Pattern Editor Software.
Opt. 2M - Rack Mounts - 2 rackmount kits
Opt. A3 - Australian 240 V, 50 Hz.
gB1400T
1400 Mb/s BERT Pattern Generator.
Opt. 02 - 75 Ohm Pattern Generator Only.
Opt. 05 - BURST Mode Pattern Generator Only.
Opt. 07 - Positive ECL Pattern Generator Only
Opt. 08 - 1-Mbit RAM WORD, Generator Only, w/ PC Pattern Edit software
Opt. 1M - Rack Mount.
Opt. A3 - Australian 240 V, 50 Hz.
gB1400R
1400 Mb/s BERT Error Detector.
Opt. 02 - 75 Ohm Error Detector Only.
Opt. 05 - BURST Mode Error Detector Only.
Opt. 08 - 1-Mbit RAM WORD, Detector Only w/ PC Pattern Edit Software
Opt. 1M - Rack Mount.
Opt. A3 - Australian 240 V, 50 Hz
1-4 GB1400 User Manual
Getting Started
GB Comparison
Feature
Transmitter
Frequency range
Internal Clock Source
External Clock
External Clock w/Burst Mode
Freq Resolution CR/LF
(Internal Clock)
Clock /Data
Output Amplitude
Clock/Data
Output Offset
Clock/Data Threshold
Resolution
Std. Programmable Memory 16 bits 128 Kbits 16 bits
Optional Memory 128 Kbits none 1 Mbit
PRBS Patterns (2n-1) 7,15,17,20,23 7,15,17,20,23 7,15,17,20,23
Burst Mode New Line
(External Clk Only)
Receiver
Frequency range
w/Burst Mode
Burst Mode (Ext Clk Only) Standard Feature Standard Feature Optional Feature
Clock/Data Input levels (max) 500 mV to 6.0 V p-p 500 mV to 6.0 V p-p 500 mV to 2.0 V p-p
Clock Input Threshold -3.00 to +4.5 V -3.00 to +4.5 V Fixed threshold levels
Data Input Threshold -3.00 to +4.5 V -3.00 to +4.5 V -1.5V to 1.0 V
Clock/Data Threshold
Resolution
Clock/Data Input Terminations GND, AC, -2V, +3V GND, AC, -2V, +3V GND, AC, -2V
Single-Ended operation Automatic selection Automatic selection Requires external
Clk/Data Delay Range /
Resolution
1
GB660/CSA907A
Tx and Rx
150 kHz to 700 MHz
150 kHz to 700 MHz
1
150 kHz to 700 MHz
1 kHz 1 kHz 1 kHz (was 10 kHz)
500mV to 2.0 V 500mV to 2.0 V 500mV to 2.0 V
-2.0V to +1.8 V -2.0V to +1.8 V -2.0V to +1.0 V
50 mV steps 50 mV steps 50 mV steps
Standard Feature Standard Feature Optional Feature
150 kHz to 705 MHz
150 kHz to 705 MHz
50 mV steps 50 mV steps 50 mV steps
±4 ns in 100 pS
steps
GB700
Tx and Rx
150 kHz to 705 MHz
150 kHz to 705 MHz
150 kHz to 705 MHz
150 kHz to 705 MHz
150 kHz to 705 MHz
±4 ns in 20 pS steps ±4 ns in 5 pS steps
GB1400
Tx and Rx
1 MHz to 1405 MHz
1 MHz to 1405 MHz
150 kHz to 1405 MHz
-2.0V to +1.8 V with
PECL opt.
1 MHz to 1405 MHz
150 kHz to 1405 MHz
2
cable
Note 1 Burst mode operation requires ECL levels and is DC coupled
Note 2 Single-ended operation requires ext. cable connection from rear panel DATA THRESHOLD SMA
GB1400 User Manual 1-5
Getting Started
GB1400 Instrument Configurations - Standard and Burst Option
GB1400 instruments are sold with and without the BURST option. To determine if the burst option is
installed in a GB1400, press the F1 key several times until you get to the UTIL menu. Then select the
OPTION menu. The OPTIONS menu will tell you if the Burst option is installed in the unit. External
indications of the BURST option are unique labels for both transmitter and receiver. See a write-up on
Burst Mode at the end of the Functional Overview section of Chapter 2.
GB1400 with no Burst Option Standard instrument configuration
All standard configuration GB1400 Generators (no burst option) have an AC coupled external clock
input. All standard configuration GB1400 Analyzers (no burst option) have AC coupled paths in the
receiver clock input circuitry.
GB1400 with Burst Option
When the BURST option is installed in the GB1400, the AC coupled paths in both transmitter and
receiver are eliminated. This will also change several specifications listed in the table below. External
clock inputs to the GB1400 transmitter must be ECL levels when the BURST option is installed. Clock
inputs into the GB1400 receiver must be ECL levels and are terminated into 50 Ohms to -2V.
GB1400 Clock Signals for Standard and Burst and Instruments
Standard Coupling Burst (Option) Coupling
GB1400 TX
External Clock Input 50 Ohm, AC coupled,
2V max
GB1400 RX
Clock Input 50 Ohm, AC coupled,
2.0V max
50 Ohm to -2V, DC coupled,
ECL levels
50 Ohm to -2V, DC coupled,
ECL levels
1-6 GB1400 User Manual
Initial Self-Check Procedure
You may perform the following procedure as an initial self-check of your
GB1400 Generator and Analyzer. It is also a useful introduction to the basic
features and operation of the GB1400.
The fan openings of the GB1400 needs 2-inches of clearance for proper
ventilation.
Procedure
1. Make sure both the Generator and Analyzer are equipped with the proper
fuse.
2. Make sure that the Generator and Analyzer rear-panel power switches
are ON, and that their front-panel power switches are in the STBY
position.
3. Plug both instruments into grounded (three-conductor) AC power outlets.
4. Connect a 50-Ohm SMA cable from the Generator CLOCK output to the
Analyzer CLOCK input. If using 75-Ohm option, use &5 OHM
SMA/BNC cable.
Getting Started
5. Connect a 50-Ohm SMA cable from the Generator DATA output to the
Analyzer DATA input.
6. Connect a 50-Ohm SMA cable from the Analyzer rear panel DATA
THRESHOLD output to the Analyzer DATA BAR input (required for
single-ended data inputs).
7. Power the Generator while pressing and holding its VIEW ANGLE,
MSB 1 and (PATTERN) CLEAR keys simultaneously. Release the key
after the message Default Settings appears in the display. Repeat this
procedure with the Analyzer. This will force both the Generator and
Analyzer to power up using factory default settings.
8. Set up the Generator clock and data outputs using controls in the
OUTPUT box as follows:
Set this parameter… to this value … using this procedure.
DATA amplitude. 2 volts Press the DATA key.
Press AMPLITUDE up/down keys until
data amplitude is set to 2.00V.
DATA baseline offset -1 volt Press BASELINE OFFSET up/down keys
until data baseline offset is set to -1.00V.
CLOCK amplitude 2 volts Press CLOCK.
Press AMPLITUDE up/down keys until
clock amplitude is set to 2.00V.
CLOCK baseline offset -1 volt Press BASELINE OFFSET up/down keys
until clock baseline OFFSET is set to
-1.00V.
GB1400 User Manual 1-7
Getting Started
9. Set Generator pattern to a 223-1 bit PRBS using controls in the
PATTERN box as follows:
a. Press PRBS.
b. Press the pattern up/down keys until PATTERN is set to PN 23.
10. Verify that the Generator error injection rate is off. If the LED in the
error inject RATE key is on, then press RATE one or more times until it
turns off.
11. Verify that the Analyzer auto-search function is enabled. If the LED in
the AUTO SEARCH key is off, then press AUTO SEARCH one time to
turn it on. At this point, verify that the green LOCK LED in the
Analyzer SYNC box is on.
12. Zero all Analyzer error counts by pressing CLEAR in the ERROR
DETECTION group.
13. Reset all Analyzer history LEDs by pressing CLEAR in the ERROR
HISTORY group.
14. Verify GB1400 Analyzer can detect errors by pressing the Generator
error inject SINGLE key several times. Verify that the Number of Errors
count displayed by the Analyzer increments each time the Generator
SINGLE key is pressed.
In effect you are now performing a bit error rate test on the test cables connecting
the GB1400 Generator and Analyzer. In an actual BER test, GB1400 Generator
clock and data outputs would be connected to inputs on a "device under test"
(DUT) while GB1400 Analyzer inputs would be connected to outputs on the
DUT.
1-8 GB1400 User Manual
Operating Basics
Functional Overview
This section describes how to use and navigate through the basic functions of the
GB1400, including:
• BERT Basics
• Controls, indicators and connectors
• Display Formats
• Outputs and Inputs
Also in this section is:
• Tutorial - "Understand GB1400 instrument setup for BER testing using
PRBS patterns";
• Application Note - Auto Search Synchronization with GB1400; and,
• Application Example - GB700/ GB1400 Optical component test.
GB1400 User Manual 2-1
Functional Overview
BERT Basics - GB1400
The GB1400 Generator and Analyzer together comprise a 1400 Mb/s, serial, bit
error rate test system or BERT.
A BERT is an instrument designed to measure the bit error rate (BER)—or more
generally, the error performance—of a digital communications device, module, or
system.
A typical BERT application, for example, would be to measure the error
performance of the electrical-to-optical (E/O) and optical-to-electrical (O/E)
output modules of a high-speed fiber optic transmission system (FOTS), as
shown in the figure below.
GB1400 Generator GB1400 Analyzer
CLOCK DATA
OUT OUT
E/O
O/E
CLOCK DATA
IN IN
Figure 2- 1. Example, BERT Application
The GB1400 is described as a serial BERT because it is designed to test one
digital path at a time. The term serial also distinguishes the GB1400 from
parallel BERTs, such as the Tektronix MB100, which is designed to test multiple
digital signal paths simultaneously.
The GB1400 Generator, also known as the transmitter or "Tx", can generate
various test patterns, including pseudo-random bit sequences (PRBS) and userdefined word patterns. The Generator output consists of a two level, non-return to
zero (NRZ) data signal and its associated clock signal, as illustrated in Figure
2-2. In the NRZ format, the data signal remains at either a logic "1" or logic "0"
level for the entire duration of each bit time slot, except for a small transition
period between time slots containing different data. The corresponding clock
signal is a nominal "square wave" whose frequency defines the bit rate of the test
signal.
2-2 GB1400 User Manual
Functional Overview
Falling edge of CLOCK
in middle of DATA "eye"
Rising edge of CLOCK Coincident with DATA transitions
CLOCK
DATA
Figure 2- 2. Nominal Generator NRZ Data and Clock Output
Waveforms
The nominal Generator clock/data phase relationship is fixed so that the falling
edges of the clock signal occur in the middle of bit time slots of the data signal.
The amplitude and baseline offset of the Generator's clock and data outputs are
adjustable to insure compatibility with a wide range of input circuit designs and
logic families including ECL, positive ECL, and GaAs.
The GB1400 Analyzer, also known as the receiver or "Rx", can terminate and
analyze the NRZ output of a digital device, module, or system being tested by the
GB1400 Generator or an equivalent signal source. The decision voltage or
threshold of the Analyzer DATA and CLOCK inputs can be adjusted to
accommodate different logic families. The Analyzer can also add a variable
amount of delay to the input data signal to accommodate different clock/data
phase relationships at the output of the device under test.
The primary measurements made by the GB1400 Analyzer are bit errors and bit
error rate.
GB1400 User Manual 2-3
Functional Overview
Controls, Indicators and Connectors
The first four figures in this section identify the controls, indicators and
connectors located on the front and rear panels of the GB1400 Generator (Tx)
and GB1400 Analyzer (RX).
VIEW
ANGLE
FREQUENCY (kHz)
MEMORY
PATTERN
gigaBERT1400 GENERATOR
OUTPUT
AMPL
OFFSET
ERROR INJECT
RATE SINGLE
PANEL
LOCK
GPIB
ADDR
LOCAL
REMOTE
POWER
ON
OFF
CLOCK
FREQUENCY
STEP
RECALL SAVE
EXT
INPUT
50 Ohm 2 V Max
PRBS
WORD
RECALL SAVE
PATTERN SYNC CLOCK/4 CLOCK
(2) (1)
50 Ohm SOURCE
PATTERN
WORD
F1 F2 F3 F4
LENGTH
BIT
MSB
1 2 3 4 5 6 7 8
(1) With Option 2, these outputs are 75 Ohm.
(2) With Option 5, the input is ECL levels only.
Figure 2- 3. Front Panel, GB1400 Generator (Tx)
PHASE A PHASE B CLOCK/2 ERROR INJECT DATA INHIBIT
CLEAR SET CLOCK DATA
OUTPUT
CLOCK
50 Ohm SOURCE
RS-232C
INVERT
DATA
(D-INV)
DATA
OUTPUT
AMPLITUDE
GPIB
OFFSET
DATA
WARNING
ELECTRICAL SHOCK HAZARD
THIS INSTRUMENT MUST BE GROUNDED
DO NOT OPEN INSTRUMENT REFER SERVICING TO
QUALIFIED PERSONNEL
DISCONNECT POWER CORD BEFORE REPLACING
FOR CONTINUED FIRE PRODUCTION REPLACE ONLY
INPUT MAX LINE
VOLTAGE RANGE POWER FUSE
115 90-132V 175W 5A SLOBLO
230 180-250V 175W 5A SLOBLO
AUTO SELECT FREQUENCY 47-63 Hz
FUSE
WITH SPECIFIED FUSES
AC-LINE
Figure 2- 4. Rear Panel, GB1400 Generator (Tx)
2-4 GB1400 User Manual
Loading...