Agilent Technologies 33120A User manual

Service Guide
Publication Number 33120-90017 (order as 33120-90104 manual set)
Edition 6, March 2002
©Copyright Agilent Technologies, Inc. 1994-2002
For Safety information, Warranties, and Regulatory information,
see the last page in this manual.
Agilent 33120A
15 MHz Function /
Arbitrary Waveform Generator
Cover Page for Web Version ONLY (Service Guide)

The Agilent Technologies 33120A is a high-performance 15 MHz
synthesized function generator with built-in arbitrary waveform
capability. 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 40 MSa/s arbitrary waveform capability
Easy-to-use knob input
Highly visible vacuum-fluorescent display
Instrument state storage
Portable, ruggedized case with non-skid feet
Flexible system features
Four downloadable 16,000-point arbitrary waveform memories
GPIB (IEEE-488) interface and RS-232 interface are standard
SCPI (Standard Commands for Programmable Instruments) compatibility
Agilent IntuiLink Arb Waveform Generation Software for
Microsoft®Windows®
Warning The procedures in this manual are intended for use by qualified,
service-trained personnel only.
Agilent 33120A
15 MHz Function /
Arbitrary Waveform Generator
Note: Unless otherwise indicated, this manual applies to all Serial Numbers.
Page 1 (Service Guide)

The Front Panel at a Glance
1Function / Modulation keys
2Menu operation keys
3Waveform modify keys
4Single / Internal Trigger key
(Burst and Sweep only)
5Recall / Store instrument state key
6 Enter Number key
7 Shift / Local key
8 Enter Number “units” keys
2

Front-Panel Number Entry
Increments the flashing digit.
Decrements the flashing digit.
Moves the flashing digit to the right.
Moves the flashing digit to the left.
Use “Enter” for those operations that do not
require units to be specified (AM Level,
Offset, % Duty, and Store/Recall State).
You can enter numbers from the front-panel using one of three methods.
Use the arrow keys to edit individual digits.
Use the “Enter Number” mode to enter a number with the appropriate units.
Use the knob and the arrow keys to modify the displayed number.
3

The Front-Panel Menu at a Glance
The menu is organized in a top-down tree structure with three levels.
A: MODulation MENU
1: AM SHAPE Õ 2: AM SOURCE Õ 3: FM SHAPE Õ 4: BURST CNT Õ 5: BURST RATE Õ
Õ 6: BURST PHAS Õ 7: BURST SRC Õ 8: FSK FREQ Õ 9: FSK RATE Õ 10: FSK SRC
B: SWP (Sweep) MENU
1: START F Õ 2: STOP F Õ 3: SWP TIME Õ 4: SWP MODE
C: EDIT MENU*
1: NEW ARB Õ [ 2: POINTS ] Õ [ 3: LINE EDIT ] Õ [ 4: POINT EDIT ] Õ [ 5: INVERT ] Õ [ 6: SAVE AS ] Õ 7: DELETE
* The commands enclosed in square brackets ( [ ] ) are “hidden” until you make a selection from the
NEW ARB command to initiate a new edit session.
D: SYStem MENU
1: OUT TERM Õ 2: POWER ON Õ 3: ERROR Õ 4: TEST Õ 5: COMMA Õ 6: REVISION
E: Input / Output MENU
1: HPIB ADDR Õ 2: INTERFACE Õ 3: BAUD RATE Õ 4: PARITY Õ 5: LANGUAGE
F: CALibration MENU*
1: SECURED or [ 1: UNSECURED ] Õ [ 2: CALIBRATE ] Õ 3: CAL COUNT Õ 4: MESSAGE
*The commands enclosed in square brackets ( [ ] ) are “hidden” unless the function generator
is UNSECURED for calibration.
4

Display Annunciators
Adrs
Rmt
Trig
AM
FM
Ext
FSK
Burst
Swp
ERROR
Offset
Shift
Num
Arb
Function generator is addressed to listen or talk over a remote interface.
Function generator is in remote mode (remote interface).
Function generator is waiting for a single trigger or external trigger (Burst, Sweep).
AM modulation is enabled.
FM modulation is enabled.
Function generator is set for an external modulation source (AM, FSK, Burst).
FSK (frequency-shift keying) modulation is enabled.
Burst modulation is enabled.
Sweep mode is enabled.
Hardware or remote interface command errors are detected.
The waveform is being output with an offset voltage.
“Shift” key has been pressed. Press “Shift” again to turn off.
“Enter Number” mode is enabled. Press “Shift-Cancel” to disable.
Arbitrary waveform function is enabled.
Sine waveform function is enabled.
Square waveform function is enabled.
Triangle waveform function is enabled.
Ramp waveform function is enabled.
To review the display annunciators, hold down the Shift key as you
turn on the function generator.
5

The Rear Panel at a Glance
1Chassis ground
2Power-line fuse-holder assembly
3Power-line voltage setting
4AM modulation input terminal
5External Trigger / FSK / Burst modulation
input terminal
6GPIB (IEEE-488) interface connector
7 RS-232 interface connector
Use the front-panel Input / Output Menu to:
 Select the GPIB or RS-232 interface (see chapter 4 in User’s Guide).
 Set the GPIB bus address (see chapter 4 in User’s Guide).
 Set the RS-232 baud rate and parity (see chapter 4 in User’s Guide).
6

In This Book
Specifications Chapter 1 lists the function generator’s specifications
and describes how to interpret these 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 block and circuit level theory
related to the operation the function generator.
Service Chapter 6 provides guidelines for returning your function
generator to Agilent for servicing, or for servicing it yourself.
Replaceable Parts Chapter 7 contains a detailed parts lists of the
function generator.
Schematics Chapter 8 contains the function generator’s block diagram,
schematics, disassembly drawings, and component locator drawings.
For information on using the Phase-Lock Option for the 33120A, refer to
the User’s and Service Guide included with the Option 001.
If you have questions relating to the operation of the 33120A,
call 1-800-452-4844 in the United States, or contact your nearest
Agilent Technologies Sales Office.
If you believe your 33120A has failed, refer to “Operating Checklist”,
“Types of Service Available”, and “Repackaging for Shipment” at the
beginning of chapter 6.
7

8

Contents
Contents
Chapter 1 Specifications
Chapter 2 Quick Start
To prepare the function generator for use 21
If the function generator does not turn on 22
To adjust the carrying handle 24
To set the output frequency 25
To set the output amplitude 26
To set a dc offset voltage 27
To set the duty cycle 28
To output a stored arbitrary waveform 29
To output a dc voltage 30
To store the instrument state 31
To rack mount the function generator 33
Chapter 3 Front-Panel Menu Operation
Front-panel menu reference 37
A front-panel menu tutorial 39
To select the output termination 44
To output a modulated waveform 45
To unsecure the function generator for calibration 47
Chapter 4 Calibration Procedures
Agilent Calibration Services 51
Calibration Interval 51
Time Required for Calibration 51
Automating Calibration Procedures 52
Recommended Test Equipment 52
Test Considerations 53
Performance Verification Tests 54
Frequency Verification 56
Function Gain and Linearity Verification 56
DC Function Offset Verification 57
AC Amplitude Verification 57
Amplitude Flatness Verification 60
AM Modulation Depth Verification 61
Optional Performance Verification Tests 62
9

Chapter 4 Calibration Procedures (continued)
Calibration Security Code 64
Calibration Count 66
Calibration Message 66
General Calibration/Adjustment Procedure 67
Aborting a Calibration in Progress 69
Frequency and Burst Rate Adjustment 69
Function Gain and Linearity Adjustment 70
AC Amplitude Adjustment (High-Z) 70
Modulation Adjustment 72
AC Amplitude Adjustment (50W) 73
DC Output Adjustment 76
Duty Cycle Adjustment 77
AC Amplitude Flatness Adjustment 77
Output Amplifier Adjustment (Optional) 80
Error Messages 81
Chapter 5 Theory of Operation
Block Diagram Overview 85
Output Attenuator 86
Output Amplifier 87
AM Modulation 89
Pre-attenuator 90
Square Wave and Sync 90
Filters 92
Waveform DAC/Amplitude Leveling/Waveform RAM 93
Direct Digital Synthesis (DDS ASIC) 95
System DACs 96
Floating Logic 97
Earth-Referenced Logic 98
Power Supplies 98
Display and Keyboard 100
Contents
Contents
10

Contents
Chapter 6 Service
Operating Checklist 103
Types of Service Available 104
Repackaging for Shipment 105
Cleaning 105
Electrostatic Discharge (ESD) Precautions 106
Surface Mount Repair 106
To Replace the Power-Line Fuse 107
To Replace the Output Protection Fuse (F801) 107
Troubleshooting Hints 108
Self-Test Procedures 110
Chapter 7 Replaceable Parts
Replaceable Parts 113
Chapter 8 Schematics
33120A Block Diagram 129
Mechanical Disassembly 130
Floating Logic Schematic 131
Digital Waveform Data Synthesis 132
System DAC Schematic 133
Waveform DAC Schematic 134
Filters Schematic 135
Sync, Square Wave, and Attenuator Schematic 136
Output Amplifier Schematic 137
Output Attenuator Schematic 138
Earth Reference Logic Schematic 139
Power Supplies Schematic 140
Display and Keyboard Schematic 141
33120-66521 Component Locator Diagram 142
33120-66502 Component Locator Diagram 143
Contents
11

Contents
12

1
Specifications
1

WAVEFORMS
Standard Waveforms:
Arbitrary Waveforms:
Waveform Length:
Amplitude Resolution:
Sample Rate:
Non-Volatile Memory:
Sine, Square, Triangle,
Ramp, Noise, DC volts,
Sine(x)/x, Negative Ramp,
Exponential Rise,
Exponential Fall, Cardiac
8 to 16,000 points
12 bits (including sign)
40 MSa / sec
Four 16,000-point waveforms
FREQUENCY CHARACTERISTICS
Sine:
Square:
Triangle:
Ramp:
Noise (Gaussian):
Arbitrary Waveforms:
8 to 8,192 points:
8,193 to 12,287 points:
12,288 to 16,000 points:
Resolution:
Accuracy:
Temperature Coefficient:
Aging:
100
m Hz –15 MHz
100
m Hz –15 MHz
100
m Hz –100 kHz
100
m Hz –100 kHz
10 MHz bandwidth
100
m Hz –5 MHz
100
m Hz –2.5 MHz
100
m Hz –200 kHz
10
m Hz or 10 digits
10 ppm in 90 days,
20 ppm in 1 year,
18
 C –28  C
< 2 ppm /
 C
< 10 ppm / yr
SINEWAVE SPECTRAL PURITY (into 50 W )
Harmonic Distortion
DC to 20 kHz:
20 kHz to 100 kHz:
100 kHz to 1 MHz:
1 MHz to 15 MHz:
Total Harmonic Distortion
DC to 20 kHz:
Spurious (non-harmonic)
Output (DC to 1 MHz):
Output (> 1 MHz):
Phase Noise:
-70 dBc
-60 dBc
-45 dBc
-35 dBc
< 0.04%
< -65 dBc
< -65 dBc + 6 dB/octave
< -55 dBc in a 30 kHz band
SIGNAL CHARACTERISTICS
Squarewave
Rise/Fall Time:
Overshoot:
Asymmetry:
Duty Cycle:
Triangle, Ramp, Arb
Rise/Fall Time:
Linearity:
Settling Time:
Jitter:
< 20 ns
< 4%
1% + 5 ns
20% to 80% (to 5 MHz)
40% to 60% (to 15 MHz)
40 ns (typical)
< 0.1% of peak output
< 250 ns to 0.5% of final value
< 25 ns
OUTPUT CHARACTERISTICS (1)
Amplitude (into 50
W ): (2)
Accuracy (at 1 kHz):
Flatness
< 100 kHz:
100 kHz to 1 MHz:
1 MHz to 15 MHz:
1 MHz to 15 MHz:
Offset (into 50
W ): (3)
Accuracy:
(4)
Output Impedance:
Resolution:
Output Units:
Isolation:
Protection:
50 mVpp – 10 Vpp
 1% of specified output
(sine wave relative to 1 kHz)
 1% (0.1 dB)
 1.5% (0.15 dB)
 2% (0.2 dB) Ampl  3Vrms
 3.5% (0.3 dB) Ampl < 3Vrms
 5 Vpk ac + dc
 2% of setting + 2 mV
50 ohms fixed
3 digits, Amplitude and Offset
Vpp, Vrms, dBm
42 Vpk maximum to earth
Short-circuit protected
 15 Vpk overdrive < 1 minute
(1) Add 1/10th of output amplitude and offset specification
per
 C for operation outside of 18  C to 28  C range
(1-year specification).
(2) 100 mVpp –20 Vpp amplitude into open-circuit load.
(3) Offset
 2 X peak-to-peak amplitude.
(4) For square wave outputs, add 2% of output amplitude
additional error.
Chapter 1 Specifications
Agilent 33120A Function Generator
14

MODULATION CHARACTERISTICS SYSTEM CHARACTERISTICS
AM Modulation
Carrier -3 dB Freq:
Modulation:
Frequency:
Depth:
Source:
FM Modulation
Modulation:
Frequency:
Peak Deviation:
Source:
Burst Modulation
Carrier Frequency:
Count:
Start Phase:
Internal Rate:
Gate Source:
Trigger Source:
FSK Modulation
Frequency Range:
Internal Rate:
Source:
10 MHz (typical)
Any internal waveform plus Arb
10 mHz to 20 kHz (
 0.05% to
2.5 kHz, then decreases linearly
to
 0.4% at upper limit)
0% to 120%
Internal / External
Any internal waveform plus Arb
10 mHz to 10 kHz (
 0.05% to
600 Hz, then decreases linearly
to
 0.8% at upper limit)
10 mHz to 15 MHz
Internal Only
5 MHz max.
1 to 50,000 cycles, or Infinite
-360
 to +360 
10 mHz to 50 kHz  1%
Internal or External Gate (1)
Single, External, or Internal Rate
10 mHz to 15 MHz (
 0.05% to
600 Hz, then decreases linearly
to
 4% at upper limit)
10 mHz to 50 kHz
Internal / External (1 MHz max.)
Configuration Times (2)
Function Change: (3)
Frequency Change:
(3)
Amplitude Change:
Offset Change:
Select User Arb:
Modulation Parameter Change:
80 ms
30 ms
30 ms
10 ms
100 ms
< 350 ms
FREQUENCY SWEEP
Type:
Direction:
Start F / Stop F:
Time:
Source:
Linear or Logarithmic
Up or Down
10 mHz to 15 MHz
1 ms to 500 sec
 0.1%
Single, External, or Internal
REAR-PANEL INPUTS
External AM
Modulation:
External Trigger/FSK
Burst Gate: (1)
Latency:
Jitter:
 5 Vpk = 100% Modulation
5 k
W Input Resistance
TTL (low true)
1.3
m s
25 ns
Arb Download Times over GPIB:
Arb Length Binary ASCII Integer ASCII Real (4)
16,000 points 8 sec 81 sec 100 sec
8,192 points 4 sec 42 sec 51 sec
4,096 points 2.5 sec 21 sec 26 sec
2,048 points 1.5 sec 11 sec 13 sec
Arb Download Times over RS-232 at 9600 Baud: (5)
Arb Length Binary ASCII Integer ASCII Real (6)
16,000 points 35 sec 101 sec 134 sec
8,192 points 18 sec 52 sec 69 sec
4,096 points 10 sec 27 sec 35 sec
2,048 points 6 sec 14 sec 18 sec
(1) Trigger source ignored when External Gate is selected.
(2) Time to change parameter and output the new signal.
(3) Modulation or sweep off.
(4) Times for 5-digit and 12-digit numbers.
(5) For 4800 baud, multiply the download times by two;
For 2400 baud, multiply the download times by four, etc.
(6) Time for 5-digit numbers. For 12-digit numbers,
multiply the 5-digit numbers by two.
1
Chapter 1 Specifications
Agilent 33120A Function Generator
15

GENERAL SPECIFICATIONS
Power Supply: (1)
Power-Line Frequency:
Power Installation:
Power Consumption:
Operating Environment:
Storage Environment:
State Storage Memory:
Dimensions (W x H x D)
Bench Top:
Rack Mount:
Weight:
100V / 120V / 220V / 240V  10%
(switch selectable)
50 Hz to 60 Hz
 10% and
400 Hz
 10%. Automatically
sensed at power-on.
CAT II
50 VA peak (28 W average)
0
 C to 55  C
80% Relative Humidity to 40
 C
Indoor or sheltered location
-40
 C to 70  C
Power-off state automatically
saved. Three (3) User-
Configurable Stored States,
Arbitrary waveforms stored
separately.
254.4 mm x 103.6 mm x 374 mm
212.6 mm x 88.5 mm x 348.3 mm
4 kg (8.8 lbs)
Safety Designed to:
EMC:
Vibration and Shock:
Acoustic Noise:
Warm-Up Time:
Warranty:
Remote Interface:
Programming Language:
Accessories Included:
EN61010, CSA1010, UL-1244
EN61326, 1:1997 + 1A:1998
MIL-T-28800E, Type III, Class 5
(data on file)
30 dBa
1 hour
3 years standard
IEEE-488 and RS-232 standard
SCPI-1993, IEEE-488.2
User’s Guide, Service Guide,
Quick Reference Card,
IntuiLink Arb software,
RS-232 cable, Test Report,
and power cord.
(1) For 400 Hz operation at 120 Vac, use the 100 Vac
line-voltage setting.
N10149
Chapter 1 Specifications
Agilent 33120A Function Generator
16

PRODUCT DIMENSIONS
TOP
All dimensions are
shown in millimeters.
1
Chapter 1 Specifications
Agilent 33120A Function Generator
17

18