Service GuidePublication Number 33250-90011 (order as 33250-90100 manual set)Edition 2, March 2003 Copyright Agilent Technologies, Inc. 2000, 2003For Safety information, Warranties, and Regulatory information,see the pages following the Index.Agilent 33250A80 MHz Function /Arbitrary Waveform Generator

Agilent 33250A at a GlanceThe Agilent Technologies 33250A is a high-performance 80 MHzsynthesized function generator with built-in arbitrary waveform andpulse capabilities. Its combination of bench-top and system featuresmakes this function generator a versatile solution for your testingrequirements 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 feetFlexible 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) compatibilityNote: Unless otherwise indicated, this manual applies to all Serial Numbers.2

The Front Panel at a Glance123456Graph Mode/Local KeyMenu Operation SoftkeysWaveform Selection KeysKnobModulation/Sweep/Burst MenusState Storage Menu78910Utility MenuInstrument Help Topic MenuOutput Enable/Disable KeyManual Trigger Key (used forSweep and Burst only)11 Cursor KeysNote: To get context-sensitive help on any front-panel key or menu softkey,press and hold down that key.3

The Front-Panel Display at a GlanceMenu atusDisplayIconNumericReadoutSoftkey LabelsGraph ModeTo enter the Graph Mode, press theParameterNamekey.ParameterValueSignalGroundThe softkey colors correspondto the waveform parameters.4

Front-Panel Number EntryYou 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.5

The Rear Panel at a Glance1234External 10 MHz Reference Input TerminalInternal 10 MHz Reference Output TerminalRS-232 Interface ConnectorExternal Modulation Input Terminal5 Input: External Trig/FSK/Burst GateOutput: Trigger Output6 GPIB Interface Connector7 Chassis GroundUse themenu 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).WARNINGFor protection from electrical shock, the power cord ground must not bedefeated. If only a two-contact electrical outlet is available, connect theinstrument’s chassis ground screw (see above) to a good earth ground.6

In This BookSpecifications Chapter 1 lists the function generator’s specifications.Quick Start Chapter 2 prepares the function generator for use andhelps you get familiar with a few of its front-panel features.Front-Panel Menu Operation Chapter 3 introduces you to the frontpanel 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 andcircuit-level theory related to the operation of the function generator.Service Chapter 6 provides guidelines for returning your functiongenerator to Agilent Technologies for servicing, or for servicing ityourself.Replaceable Parts Chapter 7 contains a detailed parts list of thefunction generator.Backdating Chapter 8 describes the differences between this manualand older issues of this manual.Schematics Chapter 9 contains the function generator’s schematicsand 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 AgilentTechnologies Office.If your 33250A fails within three years of purchase, Agilent will eitherrepair or replace it free of charge. Call 1-877-447-7278 in the UnitedStates (and ask for “Agilent Express”) or contact your local AgilentTechnologies Office.7


ContentsChapter 1 Specifications 13Chapter 2 Quick StartTo Prepare the Function Generator for Use 21To Adjust the Carrying Handle 22To Set the Output Frequency 23To Set the Output Amplitude 24To Set a DC Offset Voltage 26To Set the Duty Cycle 27To Configure a Pulse Waveform 28To View a Waveform Graph 29To Output a Stored Arbitrary Waveform 30To Use the Built-In Help System 31To Rack Mount the Function Generator 334Chapter 3 Front-Panel Menu OperationContentsFront-Panel Menu Reference 37To Reset the Function Generator 39To Select the Output Termination 39To Read the Calibration Information 40To Unsecure and Secure for Calibration 41To Store the Instrument State 44To Configure the Remote Interface 45Chapter 4 Calibration ProceduresAgilent Technologies Calibration Services 49Calibration Interval 50Adjustment is Recommended 50Time Required for Calibration 51Automating Calibration Procedures 52Recommended Test Equipment 53Test Considerations 54Performance Verification Tests 55Internal Timebase Verification 60AC Amplitude (high-impedance) Verification 61Low Frequency Flatness Verification 620 dB Range Flatness Verification 63 10 dB Range Flatness Verification 65 20 dB Range Flatness Verification 669

ContentsContentsChapter 4 Calibration Procedures (continued)Calibration Security 68Calibration Message 70Calibration Count 70General Calibration/Adjustment Procedure 71Aborting a Calibration in Progress 72Sequence of Adjustments 72Self-Test 73Frequency (Internal Timebase) Adjustment 74Internal ADC Adjustment 75Output Impedance Adjustment 76AC Amplitude (high-impedance) Adjustment 78Low Frequency Flatness Adjustment 800 dB Range Flatness Adjustments 81 10 dB Range Flatness Adjustments 83 20 dB Range Flatness Adjustment 85Pulse Width (Trailing Edge Delay) Adjustment 87Pulse Edge Time Adjustment 88Duty Cycle Adjustment 89Output Amplifier Adjustment (Optional) 90Calibration Errors 91Chapter 5 Theory of OperationBlock Diagram 95Main Power Supply 97On-Board Power Supplies 98Waveform DAC and Filters 100Digital Waveform, Pulse, and Sync 101Digital Waveform Translator 104Amplitude Multiplier 106Main Output Circuitry 107System ADC 110System DAC 11210

ContentsChapter 5 Theory of Operation (continued)Synthesis IC 113Timebase 115Phase Locked Loops 116Clock Divider 118Trigger and Delay 120Waveform RAM 122Synchronous Multiplexer 123Main Processor 124Main Gate Array 125DSP and Gateway 126Earth-Referenced Logic 126Front Panel 1274Chapter 6 ServiceContentsOperating Checklist 130Types of Service Available 131Repackaging for Shipment 132Cleaning 132Electrostatic Discharge (ESD) Precautions 133Surface Mount Repair 133Troubleshooting Hints 134Self-Test Procedures 136Disassembly 140Chapter 7 Replaceable Parts33250-66511 Main PC Assembly (A1) 15333205-66502 Front-Panel PC Assembly (A2) 17633250A Chassis Assembly 17733250A Front-Panel Assembly 178Manufacturer’s List 179Chapter 8 Backdating 18111

ContentsContentsChapter 9 SchematicsA1 Earth Referenced Communications Schematic 185A1 Main Processor Schematic 186A1 Main Gate Array Schematic 187A1 Display Controller Schematic 188A1 DSP Schematic 189A1 Modulation Schematic 190A1 System DAC Schematic 191A1 Timebase Schematic 192A1 Phase-Locked Loops Schematic 193A1 Trigger Schematic 194A1 Clock Divider and Control Schematic 195A1 Synthesis IC Schematic 196A1 Waveform Memory Schematic 197A1 Synchronous Multiplexer Schematic 198A1 Digital Waveform and Sync Schematic 199A1 Variable-Edge Level Translation Schematic 200A1 Waveform DAC, Filters, and Comparator Schematic 201A1 Multiplier Schematic 202A1 Main Output Circuitry Schematic 203A1 Power Supply Schematic 204A2 Keyboard Schematic 205A2 Display Schematic 206A1 Component Locator (top) 207A1 Component Locator (bottom) 208A2 Component Locator (top) 209A2 Component Locator (bottom) 21012


Chapter 1 SpecificationsAgilent 33250A Function / Arbitrary Waveform Generator1WAVEFORMSSIGNAL CHARACTERISTICSStandard Waveforms:Sine, Square, Ramp,Pulse, Noise, Sin(x)/x,Exponential Rise,Exponential Fall,Negative Ramp,Cardiac, DC VoltsArbitrary WaveformsWaveform Length:Amplitude Resolution:Repetition Rate:Sample Rate:Filter Bandwidth:Non-Volatile Memory:1 to 64K points12 bits (including sign)1 µHz to 25 MHz200 MSa/s50 MHzFour 64K waveforms 1FREQUENCY CHARACTERISTICSSine:Square:Ramp:Pulse:Noise (Gaussian):Arb:1 µHz to 80 MHz1 µHz to 80 MHz1 µHz to 1 MHz500 µHz to 50 MHz50 MHz bandwidth1 µHz to 25 MHzResolution:1 µHz;except pulse, 5 digitsAccuracy (1 year):2 ppm, 18 C to 28 C3 ppm, 0 C to 55 CSquare WaveRise / Fall Time:Overshoot:Asymmetry:Jitter (rms) 2 MHz: 2 MHz:Duty Cycle 25 MHz:25 MHz to 50 MHz:50 MHz to 80 MHz:20.0% to 80.0%40.0% to 60.0%50.0% (fixed)PulsePeriod:Pulse Width:Variable Edge Time:Overshoot:Jitter (rms):20.00 ns to 2000.0 s8.0 ns to 1999.9 s5.00 ns to 1.00 ms 5%100 ppm 50 psRampLinearity:Symmetry: 0.1% of peak output0.0% to 100.0%ArbMinimum Edge Time:Linearity:Settling Time:Jitter (rms): 8 ns 4 5%1% of period 1 ns0.01% 525 ps0.1% 75 ps 10 ns 0.1% of peak output 50 ns to 0.5% offinal value30 ppm 2.5 nsSINEWAVE SPECTRAL PURITYHarmonic DistortionDC to 1 MHz:1 MHz to 5 MHz:5 MHz to 80 MHz: 3 Vpp2-60 dBc-57 dBc-37 dBc 3 Vpp-55 dBc-45 dBc-30 dBcTotal Harmonic DistortionDC to 20 kHz: 0.2% 0.1 mVrmsSpurious (non-harmonic) 3DC to 1 MHz:-60 dBc1 MHz to 20 MHz:-50 dBc20 MHz to 80 MHz:-50 dBc 6 dBc/octavePhase Noise (30 kHz band)10 MHz -65 dBc (typical)80 MHz -47 dBc (typical)141A total of four waveforms can be stored.2Harmonic distortion at low amplitudes is limited bya -70 dBm floor.3Spurious noise at low amplitudes is limited bya -75 dBm floor.4Edge time decreased at higher frequency.

Chapter 1 SpecificationsAgilent 33250A Function / Arbitrary Waveform GeneratorOUTPUT CHARACTERISTICS 1BURST2Amplitude (into 50Ω):10 mVpp to 10 VppAccuracy (at 1 kHz, 10 mVpp, Autorange On): 1% of setting 1 mVppFlatness (sinewave relative to 1 kHz, Autorange On) 10 MHz: 1% (0.1 dB) 310 MHz to 50 MHz: 2% (0.2 dB)50 MHz to 80 MHz 5% (0.4 dB)Units:Vpp, Vrms, dBm,High Level, Low LevelResolution:0.1 mV or 4 digitsOffset (into 50Ω): 5 Vpk ac dcAccuracy:1% of setting 2 mV 0.5% of amplitudeWaveform OutputImpedance:50Ω typical (fixed) 10 MΩ (output disabled)Isolation:42 Vpk max. to EarthProtection:Short-circuit protected; 4Overload relay automatically disablesmain outputWaveforms:Frequency:Burst Count:Start / Stop Phase:Internal Period:Gate Source:Trigger Source:Trigger DelayN-Cycle, Infinite:Sine, Square, Ramp,Pulse, Noise, Arb1 µHz to 80 MHz 51 to 1,000,000 cycles,or Infinite-360.0 to 360.0 1 ms to 500 sExternal TriggerSingle, External, orInternal Rate40.0 ns to 85.000 sSWEEPWaveforms:Type:Direction:Start F / Stop F:Sweep Time:Trigger:Marker:Sine, Square, Ramp, ArbLinear or LogarithmicUp or Down100 µHz to 80 MHz1 ms to 500 sSingle, External, orInternalFalling edge of Syncsignal (programmable)MODULATION CHARACTERISTICSAM ModulationCarrier Waveforms:Modulating Waveforms:Modulating Frequency:Depth:Source:FM ModulationCarrier Waveforms:Modulating Waveforms:Sine, Square, Ramp, ArbSine, Square, Ramp,Noise, Arb2 mHz to 20 kHz0.0% to 120.0%Internal / ExternalModulating Frequency:Peak Deviation:Source:Sine, Square, Ramp, ArbSine, Square, Ramp,Noise, Arb2 mHz to 20 kHzDC to 80 MHzInternal / ExternalFSKCarrier Waveforms:Modulating Waveforms:Internal Rate:Frequency Range:Source:Sine, Square, Ramp, Arb50% duty cycle square2 mHz to 100 kHz1 µHz to 80 MHzInternal / ExternalExternal Modulation InputVoltage Range: 5V full scaleInput Impedance:10 kΩFrequency:DC to 20 kHz1Add 1/10th of output amplitude and offsetspecification per C for operation outside of18 C to 28 C range (1-year specification).220 mVpp to 20 Vpp into open-circuit load.3dB rounded to 1 digit. Instrument adheresto “%” specification.4Short-circuit protected to ground at all times.5Sine and square waveforms above 25 MHz areallowed only with an “Infinite” burst count.151

Chapter 1 SpecificationsAgilent 33250A Function / Arbitrary Waveform Generator1SYSTEM CHARACTERISTICSConfiguration TImesFunction ChangeStandard: 2Pulse:Built-In Arb: 2Frequency Change:Amplitude Change:Offset Change:Select User Arb:Modulation Change:CLOCK REFERENCE(typical) 1102 ms660 ms240 ms24 ms50 ms50 ms 400 ms for 16K points 200 msArb Download Times GPIB / RS-232 (115 Kbps) 3Arb Length Binary ASCII Integer64K points 23 sec92 sec16K points6 sec23 sec8K points3 sec12 sec4K points 1.5 sec6 sec2K points 0.75 sec3 secASCII Real154 sec39 sec20 sec10 sec5 secPhase OffsetRange:Resolution:-360 to 360 0.001 External Reference InputLock Range:Level:Impedance:Lock Time:10 MHz 35 kHz100 mVpp to 5 Vpp1 kΩ nominal, ac coupled 2sInternal Reference OutputFrequency:10 MHzLevel:632 mVpp (0 dBm),nominalImpedance:50Ω nominal, ac coupledSYNC OUTPUTLevel:Impedance:TTL-compatibleinto 1 kΩ50Ω nominalTRIGGER CHARACTERISTICSTrigger InputInput Level:Slope:TTL-compatibleRising or falling(selectable) 100 ns10 kΩ, DC coupledPulse Width:Input Impedance:LatencySweep:Burst:Jitter (rms)Sweep:Burst: 10 µs (typical) 100 ns (typical)2.5 µs1 ns;except pulse, 300 psTrigger OutputLevel:Pulse Width:Maximum Rate:Fanout:TTL-compatible into 50Ω 450 ns1 MHz 4 Agilent 33250As161Time to change parameter and output new signal.2Modulation or sweep off.3Times for 5-digit integer and 12-digit real numbers.

Chapter 1 SpecificationsAgilent 33250A Function / Arbitrary Waveform GeneratorGENERAL SPECIFICATIONSPower Supply:100-240 V ( 10%)for 50-60 Hz operation,100-127 V ( 10%)for 50-400 Hz operation.IEC 60664 CAT IIPower Consumption:140 VAOperating Environment:0 C to 55 C80% R.H. to