Agilent Technologies XX3625 User manual

Service Guide
Publication Number 54845-97008
February 2001
This manual applies directly to nfiniium oscilloscopes with serial number prefixes:
•XX3625 through XX4106 and above
for information about serial numbers, see “ nstruments Covered by this Guide” in section 1.
The part number for this Service Guide
For Safety information, Warranties, and Regulatory
information, see the pages at the back of this book.
Copyright Agilent Technologies 1997-2001
All Rights Reserved.
Agilent Model 54835A/45A/46A
Oscilloscopes

ii
The Agilent Technologies Infiniium Oscilloscope Model 54835A/45A/46A at a
Glance
Ease of use with high performance
The Agilent Technologies Infiniium oscilloscopes
combine unprecedented ease-of-use with high-
performance digitizing oscilloscope functionality
to simplify your design and analysis measurement
tasks.
• Traditional oscilloscope front-panel interface
provides direct access to the controls needed
for most troubleshooting tasks
• Graphical user interface with menus,
windows, dialogs, and toolbars provides easy
access to dozens of configuration and
analysis tools, ensuring you can set up and
make the most complex measurements
• Agilent 54835A offers 4 channels, 4 GSa/s
sampling rate in 2-channel mode, 2 GSa/s
sampling rate in 4-channel mode, 1 GHz
bandwidth
• Agilent 54845A offers 4 channels, 8 GSa/s
sampling rate in 2-channel mode, 4 GSa/s
sampling rate in 4-channel mode, 1.5 GHz
bandwidth
• Agilent 54846A offers 4 channels, 8 GSa/s
sampling rate in 2-channel mode, 4 GSa/s
sampling rate in 4-channel mode, 2.25 GHz
bandwidth
Display shows waveforms and graphical user
interface
• Graphical interface allows direct interaction
with waveforms, including drag-and-drop
positioning and instant waveform zoom
• Waveforms displayed in color, making
correlation easy
• Current configuration parameters displayed
near the waveform display and are color-
coded to make identification easy
• Graphical interface menus and toolbars
simplify complex measurement setups
Horizontal controls setsweep speed and position
• Main sweep speeds from 100 ps/div to 5 s/div
• Delayed sweep speeds from 1 ps/div to main
time base setting
• Intensified waveforms on main sweep
window make it easy to see what will appear
in delayed sweep window
Acquisition and general controls start and stop
the scope and do basic setup
• Run and stop controls for continuous or
single-shot acquisitions
• Clear display before one or more acquisitions
• Default setup and Autoscale set initial
configuration
Hard disk drive and floppy disk drive for saving
and restoring setups and measurement results
• Store measurement displays for inclusion in
reports and test setup guides
• Store oscilloscope setups to repeat tests
another time
• Hard disk stores oscilloscope operating
system
Trigger setup controls set mode and basic
parameters
• Select Edge, Glitch, or Advanced Modes
• Choose input source and slope
• Set coupling for trigger
• Use graphical user interface to simplify
configuration of pattern, state, delay,
violation, and video triggers
• Use auxiliary trigger to increase triggering
flexibility
Vertical controls set input coupling, impedance,
attenuation, and position
• AC or DC input coupling
•1M
Ωor 50Ωinput impedance
• Input attenuation adjustable from 2 mV/div to
1 V/div (plus 2 V/div in 1 MΩ)
• Color-coded knobs make it easy to find the
controls that affect each waveform
Marker and quick measurements help measure
waveform parameters
• Waveform markers A and B to check voltage
or ∆−time at any point on the displayed
waveform
• Quick Meas executes up to four predefined
measurements instantly
Service Policy
The service policy of this instrument requires
replacing defective assemblies. Some
assemblies can be replaced on an exchange
basis. Items such as the vertical attenuators,
which are subject to wear and tear based on
frequency of use, are a maintenance item that
may need occasional replacement.

iii
Floppy Disk Drive
Power
Acquisition and
general controls
Horizontal
controls
Display and
Graphical
Interface
Marker and Quick
Measurements Vertical
Controls
Vertical
Inputs Auxiliary
Trigger Input
Trigger
Setup
AutoProbe
Interface

iv
n This Book
This book provides the service documentation for the Agilent Technologies 54835A/45A/46A
oscilloscope. t is divided into eight chapters.
Chapter 1 provides general information and specifications.
Chapter 2 shows you how to prepare the oscilloscope for use.
Chapter 3 gives performance tests.
Chapter 4 covers calibration and adjustment procedures, how to do them, and how often they
need to be done.
Chapter 5 provides troubleshooting information.
Chapter 6 gives the procedures and techniques for replacing assemblies and other parts.
Chapter 7 includes a list of exchange assemblies and other replaceable parts, part ordering
information, and shipping information.
Chapter 8 briefly covers the internal operation of the oscilloscope.
At the back of the book you will find Safety information, Warranties, and Regulatory information.

Contents-1
Contents
Contents 1
1 General Information 1-2
nstruments covered by this service guide 1-2
Accessories supplied 1-3
Options available 1-4
Accessories available 1-5
Specifications & characteristics 1-7
Agilent Technologies 54835A/45A/46A general characteristics 1-14
Recommended test equipment 1-16
2 Preparing for Use 2-2
Setting Up the Oscilloscope 2-3
To inspect the instrument 2-3
To connect power 2-4
To connect the mouse or other pointing device 2-5
To attach the optional trackball 2-5
To connect the keyboard 2-7
To connect to the LAN card 2-7
To connect oscilloscope probes 2-8
To connect a printer 2-9
To connect an external monitor 2-10
To connect the GP B cable 2-10
To tilt the oscilloscope upward for easier viewing 2-11
To power on the oscilloscope 2-12
To verify basic oscilloscope operation 2-13
To clean the instrument 2-14
To clean the display monitor contrast filter 2-14
3 Testing Performance 3-2
Testing nterval 3-2
Equipment Required 3-2
Self-Test Verification 3-2
Test Record 3-3
Operating Hints 3-3
Specifications 3-3
Performance Test Procedures 3-3
To test the dc calibrator 3-4
To test input resistance 3-6
To test voltage measurement accuracy 3-7
To test offset accuracy 3-11
To test bandwidth 3-13
To test time measurement accuracy 3-16
To test trigger sensitivity 3-23
4 Calibrating and Adjusting 4-2
Equipment Required 4-2
Self Calibration nterval and Hardware Adjustments 4-2

Contents
Contents–2
Mainframe Cal Factor Memory Error 4-2
Operating Hints 4-3
Loading Default Oscilloscope Settings 4-3
Loading New Software 4-3
Calibration Procedures 4-3
To check the power supply 4-4
To check the 715 Hz auxiliary output (probe compensation squarewave) 4-6
To check the flat panel display (FPD) 4-7
To run the self calibration 4-10
Troubleshooting -2
Safety 5-2
Tools Required 5-2
ESD Precautions 5-2
Keystroke Conventions 5-2
Default Setup 5-3
To install the fan safety shield 5-3
To troubleshoot the instrument 5-4
Primary Trouble solation 5-6
No Display Trouble solation 5-9
Power Supply Trouble solation 5-13
To check probe power outputs 5-16
To check the keyboard 5-17
To check the LEDs 5-19
To check the motherboard, CPU, and RAM 5-21
To check the SVGA display board video signals 5-22
To check the backlight inverter voltages 5-23
POST Code Listing (AM Motherboard only) 5-24
To configure the motherboard jumpers and set up the B OS 5-29
To troubleshoot the acquisition system 5-49
To troubleshoot attenuator failures 5-56
Software Revisions 5-59
6 Replacing Assemblies 6-2
ESD Precautions 6-2
Tools Required 6-2
To return the instrument to Agilent Technologies for service 6-3
To remove and replace the cover 6-4
To disconnect and connect Mylar flex cables 6-5
To remove and replace the AutoProbe assembly 6-6
To remove and replace the probe power and control assembly 6-8
To remove and replace the backlight inverter board 6-9
To remove and replace the front panel assembly 6-9
To remove and replace the keyboard and flat-panel display assemblies 6-12
To remove and replace the acquisition board assembly 6-14
To remove and replace the LAN interface board 6-15
To remove and replace the GP B interface board 6-16
To remove and replace the scope interface board and SVGA display board 6-17
To separate the scope interface board and SVGA display board 6-18
To remove and replace the Option 200 sound card 6-19
To remove and replace the hard disk drive 6-20

Contents
Contents–3
To remove and replace the floppy disk drive 6-21
To remove and replace the motherboard 6-21
To remove and replace the power supply 6-24
To remove and replace the fan 6-25
To remove and replace the CPU 6-26
To remove and replace RAM S MMs or SDRAM D MMs 6-27
To remove and replace an attenuator 6-28
To reset the attenuator contact counter 6-30
To remove and replace an acquisition hybrid 6-32
7 Replaceable Parts 7-2
Ordering Replaceable Parts 7-2
Power Cables and Plug Configurations 7-3
Exploded Views 7-4
Replaceable Parts List 7-15
8 Theory of Operation 8-3
Block-Level Theory 8-3
Attenuator Theory 8-7
Acquisition Theory 8-7

Contents-4

1
nstruments covered by this service guide 1-2
Accessories supplied 1-3
Options available 1-4
Accessories available 1-5
Specifications & characteristics 1-7
Agilent Technologies 54835A/45A/46A general characteristics 1-14
Recommended test equipment 1-16
General Infor ation

1–2
General Infor ation
This chapter of the Agilent Technologies Infiniium Oscilloscope Service Guide gives
you general information about the instrument. The following topics are covered in this
chapter.
• nstrument identification
• Options
• Accessories
• Specifications and characteristics
• Test equipment requirements
Instru ents covered by this service guide
On the rear panel of the instrument is a serial number label and a V N # label. The serial number
is in the form of XX00000000 while the V N # is in the form of V N # 0XX. The serial number is
composed of two parts: the first two letters and the first four numbers are the serial prefix, while
the last four numbers a re the su ffi x. The p refi x i s norma lly the s ame for all ide ntica l oscil loscop es
and changes only when a change has been made to the oscilloscope. However, the suffix is
sequentially assigned and is different for each oscilloscope. The contents of this manual applies
to oscilloscopes with serial number prefixes listed on the title page.
An oscilloscope manufactured after the printing of this manual may have a newer serial number
prefix. This newer serial prefix indicates that the oscilloscope may be different from those
described in this manual. The manual for this oscilloscope will be revised as needed. f you have
an oscilloscope with a newer serial prefix, please refer to the Agilent Technologies website and
download a newer manual edition in Adobe Acrobat (pdf) format. The Agilent Technologies
URL is: “www.agilent.com”. t will be necessary to search on a key word such as “ nfiniium
Service Guide”, and follow the links.
For additional information on configuration differences see the following sections in this service
guide:
• “To configure the motherboard jumpers and setup the B OS” in the Troubleshooting section
5 for information on determining:
•which computer configuration is contained in your oscilloscope
•setting up the BIOS correctly for that configuration
•setting the motherboard jumpers if the PC motherboard is changed.
• Replaceable Parts section 7.
This section contains exploded views for the different motherboard configurations, cabling
schemes, and outside hardware versions. The Replaceable Parts List also contains the
assembly part numbers for the different oscilloscope configurations.
Table 1-1 Oscilloscopes Covered by this Service Guide
The oscilloscope can be identified by the product number on the back panel.
Model Description
Agilent 54846A Four-channel digitizing oscilloscope with 8 GSa/s sample rate in 2-channel mode, 4
GSa/s sample rate in 4-channel mode, 2.25 GHz bandwidth
Agilent 54845A Four-channel digitizing oscilloscope with 8 GSa/s sample rate in 2-channel mode, 4
GSa/s sample rate in 4-channel mode, 1.5 GHz bandwidth
Agilent 54835A Four-channel digitizing oscilloscope with 4 GSa/s sample rate in 2-channel mode,
2 GSa/s sample rate in 4-channel mode, 1 GHz bandwidth