Agilent Technologies 33250A User manual

Agilent 33250A
80 MHz Function /
Arbitrary Waveform Generator
Service Guide
Publication Number 33250-90011 (order as 33250-90100 manual set)
Edition 2, March 2003
©Copyright Agilent Technologies, Inc. 2000, 2003
For Safety information, Warranties, and Regulatory information,
see the pages following the Index.

2
Agilent 33250A at a Glance
The Agilent Technologies 33250A is a high-performance 80 MHz
synthesized function generator with built-in arbitrary waveform and
pulse capabilities. Its combination of bench-top and system features
makes this function generator a versatile solution for your testing
requirements now and in the future.
Convenient bench-top features
• 10 standard waveforms
• Built-in 12-bit 200 MSa/s arbitrary waveform capability
• Precise pulse waveform capabilities with adjustable edge time
• LCD color display provides numeric and graphical views
• Easy-to-use knob and numeric keypad
• Instrument state storage with user-defined names
• Portable, ruggedized case with non-skid feet
Flexible system features
• Four downloadable 64K-point arbitrary waveform memories
• GPIB (IEEE-488) interface and RS-232 interface are standard
• SCPI (Standard Commands for Programmable Instruments) compatibility
Note: Unless otherwise indicated, this manual applies to all Serial Numbers.

3
The Front Panel at a Glance
Note: To get context-sensitive help on any front-panel key or menu softkey,
press and hold down that key.
1Graph Mode/Local Key
2Menu Operation Softkeys
3Waveform Selection Keys
4Knob
5Modulation/Sweep/Burst Menus
6State Storage Menu
7Utility Menu
8Instrument Help Topic Menu
9Output Enable/Disable Key
10 Manual Trigger Key (used for
Sweep and Burst only)
11 Cursor Keys

4
The Front-Panel Display at a Glance
Menu Mode
Trigger Output Mode
Numeric
Readout
Information Information Status
Units
Display
Icon
Softkey Labels
Graph Mode
To enter the Graph Mode, press the key.
The softkey colors correspond
to the waveform parameters.
Signal
Ground
Parameter
Name
Parameter
Value

5
Front-Panel Number Entry
You can enter numbers from the front-panel using one of two methods.
Use the knob and arrow keys to modify the displayed number.
+
Use the numeric keypad and menu softkeys to select the units.

6
The Rear Panel at a Glance
WARNING For protection from electrical shock, the power cord ground must not be
defeated. If only a two-contact electrical outlet is available, connect the
instrument’s chassis ground screw (see above) to a good earth ground.
1 External 10 MHz Reference Input Terminal
2 Internal 10 MHz Reference Output Terminal
3RS-232 Interface Connector
4External Modulation Input Terminal
5 Input: External Trig/FSK/Burst Gate
Output: Trigger Output
6GPIB Interface Connector
7Chassis Ground
Use the menu to:
• Select the GPIB or RS-232 interface (see chapter 2 in User’s Guide).
• Select the GPIB address (see chapter 2 in User’s Guide).
• Set the RS-232 baud rate, parity, and handshake (see chapter 2 in User’s Guide).

7
In This Book
Specifications Chapter 1 lists the function generator’s specifications.
Quick Start Chapter 2 prepares the function generator for use and
helps you get familiar with a few of its front-panel features.
Front-Panel Menu Operation Chapter 3 introduces you to the front-
panel menu and describes some of the function generator’s menu features.
Calibration Procedures Chapter 4 provides calibration, verification,
and adjustment procedures for the function generator.
Theory of Operation Chapter 5 describes the block diagram and
circuit-level theory related to the operation of the function generator.
Service Chapter 6 provides guidelines for returning your function
generator to Agilent Technologies for servicing, or for servicing it
yourself.
Replaceable Parts Chapter 7 contains a detailed parts list of the
function generator.
Backdating Chapter 8 describes the differences between this manual
and older issues of this manual.
Schematics Chapter 9 contains the function generator’s schematics
and component locator drawings.
If you have questions relating to the operation of the Agilent 33250A,
call 1-800-452-4844 in the United States, or contact your nearest Agilent
Technologies Office.
If your 33250A fails within three years of purchase, Agilent will either
repair or replace it free of charge. Call 1-877-447-7278 in the United
States (and ask for “Agilent Express”) or contact your local Agilent
Technologies Office.

8

9
4
Contents
Contents
Chapter 1 Specifications 13
Chapter 2 Quick Start
To Prepare the Function Generator for Use 21
To Adjust the Carrying Handle 22
To Set the Output Frequency 23
To Set the Output Amplitude 24
To Set a DC Offset Voltage 26
To Set the Duty Cycle 27
To Configure a Pulse Waveform 28
To View a Waveform Graph 29
To Output a Stored Arbitrary Waveform 30
To Use the Built-In Help System 31
To Rack Mount the Function Generator 33
Chapter 3 Front-Panel Menu Operation
Front-Panel Menu Reference 37
To Reset the Function Generator 39
To Select the Output Termination 39
To Read the Calibration Information 40
To Unsecure and Secure for Calibration 41
To Store the Instrument State 44
To Configure the Remote Interface 45
Chapter 4 Calibration Procedures
Agilent Technologies Calibration Services 49
Calibration Interval 50
Adjustment is Recommended 50
Time Required for Calibration 51
Automating Calibration Procedures 52
Recommended Test Equipment 53
Test Considerations 54
Performance Verification Tests 55
Internal Timebase Verification 60
AC Amplitude (high-impedance) Verification 61
Low Frequency Flatness Verification 62
0 dB Range Flatness Verification 63
+10 dB Range Flatness Verification 65
+20 dB Range Flatness Verification 66

10
Contents
Contents
Chapter 4 Calibration Procedures (continued)
Calibration Security 68
Calibration Message 70
Calibration Count 70
General Calibration/Adjustment Procedure 71
Aborting a Calibration in Progress 72
Sequence of Adjustments 72
Self-Test 73
Frequency (Internal Timebase) Adjustment 74
Internal ADC Adjustment 75
Output Impedance Adjustment 76
AC Amplitude (high-impedance) Adjustment 78
Low Frequency Flatness Adjustment 80
0 dB Range Flatness Adjustments 81
+10 dB Range Flatness Adjustments 83
+20 dB Range Flatness Adjustment 85
Pulse Width (Trailing Edge Delay) Adjustment 87
Pulse Edge Time Adjustment 88
Duty Cycle Adjustment 89
Output Amplifier Adjustment (Optional) 90
Calibration Errors 91
Chapter 5 Theory of Operation
Block Diagram 95
Main Power Supply 97
On-Board Power Supplies 98
Waveform DAC and Filters 100
Digital Waveform, Pulse, and Sync 101
Digital Waveform Translator 104
Amplitude Multiplier 106
Main Output Circuitry 107
System ADC 110
System DAC 112

11
4
Contents
Contents
Chapter 5 Theory of Operation (continued)
Synthesis IC 113
Timebase 115
Phase Locked Loops 116
Clock Divider 118
Trigger and Delay 120
Waveform RAM 122
Synchronous Multiplexer 123
Main Processor 124
Main Gate Array 125
DSP and Gateway 126
Earth-Referenced Logic 126
Front Panel 127
Chapter 6 Service
Operating Checklist 130
Types of Service Available 131
Repackaging for Shipment 132
Cleaning 132
Electrostatic Discharge (ESD) Precautions 133
Surface Mount Repair 133
Troubleshooting Hints 134
Self-Test Procedures 136
Disassembly 140
Chapter 7 Replaceable Parts
33250-66511 Main PC Assembly (A1) 153
33205-66502 Front-Panel PC Assembly (A2) 176
33250A Chassis Assembly 177
33250A Front-Panel Assembly 178
Manufacturer’s List 179
Chapter 8 Backdating 181

12
Contents
Contents
Chapter 9 Schematics
A1 Earth Referenced Communications Schematic 185
A1 Main Processor Schematic 186
A1 Main Gate Array Schematic 187
A1 Display Controller Schematic 188
A1 DSP Schematic 189
A1 Modulation Schematic 190
A1 System DAC Schematic 191
A1 Timebase Schematic 192
A1 Phase-Locked Loops Schematic 193
A1 Trigger Schematic 194
A1 Clock Divider and Control Schematic 195
A1 Synthesis IC Schematic 196
A1 Waveform Memory Schematic 197
A1 Synchronous Multiplexer Schematic 198
A1 Digital Waveform and Sync Schematic 199
A1 Variable-Edge Level Translation Schematic 200
A1 Waveform DAC, Filters, and Comparator Schematic 201
A1 Multiplier Schematic 202
A1 Main Output Circuitry Schematic 203
A1 Power Supply Schematic 204
A2 Keyboard Schematic 205
A2 Display Schematic 206
A1 Component Locator (top) 207
A1 Component Locator (bottom) 208
A2 Component Locator (top) 209
A2 Component Locator (bottom) 210

1
1
Specifications

14
Chapter 1 Specifications
Agilent 33250A Function / Arbitrary Waveform Generator
1
WAVEFORMS
Standard Waveforms: Sine, Square, Ramp,
Pulse, Noise, Sin(x)/x,
Exponential Rise,
Exponential Fall,
Negative Ramp,
Cardiac, DC Volts
Arbitrary Waveforms
Waveform Length: 1 to 64K points
Amplitude Resolution: 12 bits (including sign)
Repetition Rate: 1 µHz to 25 MHz
Sample Rate: 200 MSa/s
Filter Bandwidth: 50 MHz
Non-Volatile Memory: Four 64K waveforms
1
FREQUENCY CHARACTERISTICS
Sine: 1 µHz to 80 MHz
Square: 1 µHz to 80 MHz
Ramp: 1 µHz to 1 MHz
Pulse: 500 µHz to 50 MHz
Noise (Gaussian):50 MHz bandwidth
Arb: 1 µHz to 25 MHz
Resolution: 1 µHz;
except pulse, 5 digits
Accuracy (1 year): 2 ppm, 18°C to 28°C
3 ppm, 0°C to 55°C
SINEWAVE SPECTRAL PURITY
Harmonic Distortion
Total Harmonic Distortion
DC to 20 kHz: < 0.2% + 0.1 mVrms
Spurious (non-harmonic) 3
DC to 1 MHz: -60 dBc
1 MHz to 20 MHz: -50 dBc
20 MHz to 80 MHz: -50 dBc + 6 dBc/octave
Phase Noise (30 kHz band)
10 MHz < -65 dBc (typical)
80 MHz < -47 dBc (typical)
SIGNAL CHARACTERISTICS
Square Wave
Rise / Fall Time: < 8 ns 4
Overshoot: < 5%
Asymmetry: 1% of period + 1 ns
Jitter (rms)
< 2 MHz: 0.01% + 525 ps
>2 MHz: 0.1% + 75 ps
Duty Cycle
<25 MHz: 20.0% to 80.0%
25 MHz to 50 MHz: 40.0% to 60.0%
50 MHz to 80 MHz: 50.0% (fixed)
Pulse
Period: 20.00 ns to 2000.0 s
Pulse Width: 8.0 ns to 1999.9 s
Variable Edge Time: 5.00 ns to 1.00 ms
Overshoot: < 5%
Jitter (rms): 100 ppm + 50 ps
Ramp
Linearity: < 0.1% of peak output
Symmetry: 0.0% to 100.0%
Arb
Minimum Edge Time: < 10 ns
Linearity: < 0.1% of peak output
Settling Time: < 50 ns to 0.5% of
final value
Jitter (rms): 30 ppm + 2.5 ns
_______________
1A total of four waveforms can be stored.
2Harmonic distortion at low amplitudes is limited by
a -70 dBm floor.
3Spurious noise at low amplitudes is limited by
a -75 dBm floor.
4Edge time decreased at higher frequency.
< 3 Vpp2> 3 Vpp
DC to 1 MHz:
1 MHz to 5 MHz:
5 MHz to 80 MHz:
-60 dBc
-57 dBc
-37 dBc
-55 dBc
-45 dBc
-30 dBc

15
Chapter 1 Specifications
Agilent 33250A Function / Arbitrary Waveform Generator
4
1
OUTPUT CHARACTERISTICS 1
Amplitude (into 50Ω):10 mVpp to 10 Vpp 2
Accuracy (at 1 kHz, >10 mVpp, Autorange On):
± 1% of setting ±1 mVpp
Flatness (sinewave relative to 1 kHz, Autorange On)
< 10 MHz: ± 1% (0.1 dB) 3
10 MHz to 50 MHz: ± 2% (0.2 dB)
50 MHz to 80 MHz ± 5% (0.4 dB)
Units: Vpp, Vrms, dBm,
High Level, Low Level
Resolution: 0.1 mV or 4 digits
Offset (into 50Ω): ± 5 Vpk ac + dc
Accuracy: 1% of setting + 2 mV
+ 0.5% of amplitude
Waveform Output
Impedance: 50Ωtypical (fixed)
>10 M Ω (output disabled)
Isolation: 42 Vpk max. to Earth
Protection: Short-circuit protected ;4
Overload relay auto-
matically disables
main output
MODULATION CHARACTERISTICS
AM Modulation
Carrier Waveforms: Sine, Square, Ramp, Arb
Modulating Waveforms: Sine, Square, Ramp,
Noise, Arb
Modulating Frequency: 2 mHz to 20 kHz
Depth: 0.0% to 120.0%
Source: Internal / External
FM Modulation
Carrier Waveforms: Sine, Square, Ramp, Arb
Modulating Waveforms: Sine, Square, Ramp,
Noise, Arb
Modulating Frequency: 2 mHz to 20 kHz
Peak Deviation: DC to 80 MHz
Source: Internal / External
FSK
Carrier Waveforms: Sine, Square, Ramp, Arb
Modulating Waveforms: 50% duty cycle square
Internal Rate: 2 mHz to 100 kHz
Frequency Range: 1 µHz to 80 MHz
Source: Internal / External
External Modulation Input
Voltage Range: ± 5V full scale
Input Impedance: 10 kΩ
Frequency: DC to 20 kHz
BURST
Waveforms: Sine, Square, Ramp,
Pulse, Noise, Arb
Frequency: 1 µHz to 80 MHz 5
Burst Count: 1 to 1,000,000 cycles,
or Infinite
Start / Stop Phase: -360
.0° to +360.0 °
Internal Period: 1 ms to 500 s
Gate Source: External Trigger
Trigger Source: Single, External, or
Internal Rate
Trigger Delay
N-Cycle, Infinite: 0.0 ns to 85.000 s
SWEEP
Waveforms: Sine, Square, Ramp, Arb
Type: Linear or Logarithmic
Direction: Up or Down
Start F / Stop F: 100 µHz to 80 MHz
Sweep Time: 1 ms to 500 s
Trigger: Single, External, or
Internal
Marker: Falling edge of Sync
signal (programmable)
_______________
1Add 1/10th of output amplitude and offset
specification per °C for operation outside of
18 °C to 28 °C range (1-year specification).
220 mVpp to 20 Vpp into open-circuit load.
3dB rounded to 1 digit. Instrument adheres
to “%” specification.
4Short-circuit protected to ground at all times.
5Sine and square waveforms above 25 MHz are
allowed only with an “Infinite” burst count.

16
Chapter 1 Specifications
Agilent 33250A Function / Arbitrary Waveform Generator
1
SYSTEM CHARACTERISTICS
Configuration TImes (typical) 1
Function Change
Standard: 2102 ms
Pulse: 660 ms
Built-In Arb: 2240 ms
Frequency Change: 24 ms
Amplitude Change: 50 ms
Offset Change: 50 ms
Select User Arb:
< 400 ms for < 16K points
Modulation Change: < 200 ms
Arb Download Times GPIB / RS-232 (115 Kbps) 3
TRIGGER CHARACTERISTICS
Trigger Input
Input Level: TTL-compatible
Slope: Rising or falling
(selectable)
Pulse Width: > 100 ns
Input Impedance: 10 kΩ, DC coupled
Latency
Sweep: < 10 µs (typical)
Burst: < 100 ns (typical)
Jitter (rms)
Sweep: 2.5 µs
Burst: 1 ns;
except pulse, 300 ps
Trigger Output
Level: TTL-compatible into 50 Ω
Pulse Width: > 450 ns
Maximum Rate: 1 MHz
Fanout: < 4 Agilent 33250As
CLOCK REFERENCE
Phase Offset
Range: -360 ° to +360 °
Resolution: 0.001 °
External Reference Input
Lock Range: 10 MHz ± 35 kHz
Level: 100 mVpp to 5 Vpp
Impedance: 1 k Ω nominal, ac coupled
Lock Time: < 2 s
Internal Reference Output
Frequency: 10 MHz
Level: 632 mVpp (0 dBm),
nominal
Impedance: 50 Ω nominal, ac coupled
SYNC OUTPUT
Level: TTL-compatible
into > 1 kΩ
Impedance: 50Ωnominal
_______________
1Time to change parameter and output new signal.
2Modulation or sweep off.
3Times for 5-digit integer and 12-digit real numbers.
Arb Length Binary ASCII Integer ASCII Real
64K points 23 sec 92 sec 154 sec
16K points 6 sec 23 sec 39 sec
8K points 3 sec 12 sec 20 sec
4K points 1.5 sec 6 sec 10 sec
2K points 0.75 sec 3 sec 5 sec

17
Chapter 1 Specifications
Agilent 33250A Function / Arbitrary Waveform Generator
4
1
GENERAL SPECIFICATIONS
Power Supply: 100-240 V (±10%)
for 50-60 Hz operation,
100-127 V (±10%)
for 50-400 Hz operation.
IEC 60664 CAT II
Power Consumption: 140 VA
Operating Environment: 0 °C to 55 °C
80% R.H. to 40 °C
Operating Altitude: 3000 meters
Pollution Degree: Indoor or Sheltered Use,
IEC 60664 Degree 2
Storage Temperature: -30 °C to 70 °C
Stored States: Four (4) named user
configurations
Power-On State: Default or Last
Interface: IEEE-488 and RS-232
standard
Language: SCPI-1997, IEEE-488.2
Dimensions (WxHxD)
Bench Top: 254 x 104 x 374 mm
Rack Mount: 213 x 89 x 348 mm
Weight: 4.6 kg
Safety Designed to:
EN61010-1, CSA1010.1 ,
UL-3111-1
EMC Tested to: 1 IEC-61326-1
IEC-61000-4-3 criteria B
IEC-61000-4-6 criteria B
Acoustic Noise: 40 dBA
Warm-Up Time: 1 hour
Calibration Interval: 1 year
Warranty: 3 years standard
Accessories Included: User’s Guide,
Service Guide,
Quick Reference Guide,
Test Data,
Connectivity Software,
RS-232 Cable,
Power Cord
_______________
1Radiated and conducted immunity testing:
When the product is tested at 3 V/m according
to IEC/EN 61000-4-3:1995 or tested at 3 Vrms
according to IEC/EN 61000-4-6:1996, the product
may not meet criteria A, but does meet criteria B.
This ISM device complies with Canadian ICES-001.
Cet appareil ISM est conforme à la norme NMB-001
du Canada.
N10149

18
Chapter 1 Specifications
Agilent 33250A Function / Arbitrary Waveform Generator
1
PRODUCT DIMENSIONS
254.4 mm 374.0 mm
103.6 mm
216.6 mm 348.3 mm
88.5 mm
All dimensions are
shown in millimeters.

2
2
Quick Start

20
2
Quick Start
One of the first things you will want to do with your function generator
is to become acquainted with the front panel. We have written the
exercises in this chapter to prepare the instrument for use and help
you get familiar with some of its front-panel operations. This chapter
is divided into the following sections:
• To Prepare the Function Generator for Use, on page 21
• To Adjust the Carrying Handle, on page 22
• To Set the Output Frequency, on page 23
• To Set the Output Amplitude, on page 24
• To Set a DC Offset Voltage, on page 26
• To Set the Duty Cycle, on page 27
• To Configure a Pulse Waveform, on page 28
• To View a Waveform Graph, on page 29
• To Output a Stored Arbitrary Waveform, on page 30
• To Use the Built-In Help System, on page 31
• To Rack Mount the Function Generator, on page 33