Output Amplifier | Agilent Technologies 33120A guide

Chapter 5 Theory of Operation

Output Amplifier

Output Amplifier

Block 7 on block diagram page 129; Schematic on page 137.

The output amplifier drives the function generator’s signal output through the output attenuator section. The output amplifier exhibits an approximate 35 MHz bandwidth and 1000 V/ms slew rate. AC signals originating from the DAC+ and DAC- signal paths are combined at the input of the amplifier. The output amplifier exhibits a nominal x(-10) voltage gain from its -AMP_IN input and a nominal x12 voltage gain from its +AMP_IN input. A dc offset signal, related to the front panel output offset value, is also summed with the ac signal at the input of the amplifier. A simplified block diagram of the output amplifier is shown below.

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Agilent Technologies 33120A manual Output Amplifier, Block 7 on block diagram page 129 Schematic on

Contents

Agilent 33120A MHz Function Arbitrary Waveform Generator Service GuidePage Flexible system features Convenient bench-top features Front Panel at a Glance Front-Panel Number Entry MODulation Menu Front-Panel Menu at a Glance Trig Display Annunciators Use the front-panel Input / Output Menu to Rear Panel at a Glance This Book Page Contents Contents Replaceable Parts ServiceSchematics Contents Specifications Waveforms Modulation Characteristics General Specifications Product Dimensions Page Quick Start Quick Start Connect the power cord and turn on the function generator One User’s Guide 〈 This Service GuideTo prepare the function generator for use Check the list of supplied items Verify the power-line voltage setting Verify that there is ac power to the function generatorVerify that the power-line fuse is good If the function generator does not turn on Remove the power cord . Remove To adjust the carrying handle To set the output frequency To cancel the number mode, press Shift CancelEnter the magnitude of the desired frequency Set the units to the desired value Enter the magnitude of the desired amplitude To set the output amplitude Enable the offset modify mode How to change the offset to -1.5 mVdcTo set a dc offset voltage Enter the magnitude of the desired offset Select the square wave function To set the duty cycleEnter the desired duty cycle Output the waveform with the displayed duty cycle Display the list of arbitrary waveforms To output a stored arbitrary waveformMove across to the Exprise choice Select and output the displayed arbitrary waveform Enter the magnitude of the desired voltage To output a dc voltage Turn on the state storage mode Set up the function generator to the desired configurationTo store the instrument state Save the instrument state Recall the stored instrument state Restore the instrument state To rack mount the function generator Quick Start Front-Panel Menu Operation Front-Panel Menu Operation MODulation Menu Front-panel menu reference Front-panel menu reference SYStem Menu Front-panel menu tutorial Messages Displayed During Menu Use Move across to the SYS Menu choice on this level Move across to the Power on command on this levelTurn on the menu Save the change and turn off the menu Cycle the power to restore the default valuesMove down a level to the Parameter choices Increment the first digit until 300.0 mVPP is displayed Select amplitude adjustment Move down a level and then across to the High Z choice Move down a level to the OUT Term commandTo select the output termination Use the menu to select the shape of the modulating waveform To output a modulated waveformSelect AM Set the modulation depth to 80% Move down a level verify that Sine is selectedSet the modulating frequency to 200 Hz Move across to the CAL Menu choice on this level Move down a level to the Secured commandTo unsecure the function generator for calibration Move down to the parameters level Calibration Procedures Calibration Procedures Time Required for Calibration Agilent Calibration ServicesCalibration Interval Recommended Test Equipment Automating Calibration Procedures Test Considerations Self-Test Performance Verification Tests Quick Performance Check Function Gain and Linearity Verification Frequency Verification AC Amplitude Verification DC Function Offset Verification AC Amplitude Verification Vrms 0.00035 Vrms 15.00 MHz Amplitude Flatness Verification Vrms 0.0061 Vrms AM Modulation Depth Verification Square Wave Duty Cycle Verification Optional Performance Verification Tests Distortion Verification Characters Calibration Security Code To Unsecure the Function Generator Without the Security Code Calibration Message Calibration Count Move down a level to the Unsecured command General Calibration/Adjustment ProcedureBegin the Frequency and Burst Rate adjustment procedure Move across to the Calibrate choice Calculate and save the new value Perform the next adjustment procedure Aborting a Calibration in Progress Frequency and Burst Rate Adjustment AC Amplitude Adjustment High-Z Function Gain and Linearity Adjustment AC Amplitude Adjustment High-Z Frequency Amplitude Modulation Adjustment AC Amplitude Adjustment 50W AC Amplitude Adjustment 50W Adjustment for KHz Setup DC Output Adjustment AC Amplitude Flatness Adjustment Duty Cycle Adjustment AC Amplitude Flatness Adjustment Exiting Output Amplifier Adjustment Optional Self-Test Error Messages Error MessagesSystem Error Messages Calibration Error Messages Theory of Operation Theory of Operation Self-test procedures are described in chapter This discussion pertains to the block diagram shown on Block Diagram Overview Output Attenuator Block 8 on block diagram page 129 Schematic on Output Amplifier Block 7 on block diagram page 129 Schematic on 740 R710 R717 740 R710 R711 R715 R716 R719 R720 AM Modulation Block 6 on block diagram page 129, schematic on Block 6 on block diagram page 129 Schematic onPre-attenuator Square Wave and Sync Square Wave and Sync Filters Block 5 on block diagram page 129 Schematic on Waveform DAC/Amplitude Leveling/Waveform RAM Block 4 on block diagram page 129 Schematic on Waveform DAC/Amplitude Leveling/Waveform RAM Direct Digital Synthesis DDS Asic Block 2 on block diagram page 129 Schematic on System DACs Block 3 on block diagram page 129 Schematic on Floating Logic Block 1 on block diagram page 129 Schematic on Block 9 on block diagram page 129 Schematic on Power SuppliesBlock 10 on block diagram page 129 Schematic on Earth-Referenced Logic Power Supplies See Block 11 on block diagram page 129 Schematic onDisplay and Keyboard Service Service Is the function generator inoperative? Operating ChecklistSee To prepare the function generator for use on Does the function generator fail self-test? Call 1-877-447-7278 and ask for Agilent Express Types of Service Available Agilent suggests that you always insure shipments CleaningRepackaging for Shipment Surface Mount Repair Electrostatic Discharge ESD Precautions To Replace the Output Protection Fuse F801 To Replace the Power-Line Fuse Unit Reports Error Troubleshooting HintsUnit is Inoperative Unit Fails Self-Test Power Supply Problems Power-On Self-Test Self-Test Procedures 625 112 Replaceable Parts Replaceable Parts Main PC Assembly 116 117 118 119 120 121 122 123 Display and Keyboard PC Assembly 33120A Mainframe Manufacturer’s List Schematics8 Schematics Block Diagram Pull Off Handle Loosen Captive Sheet 1 132 Sheet 3 Sheet 4 Waveform DAC Schematic 134 Sheet 5 136 Sheet 7 Sheet 8 Output Attenuator Schematic 138 Sheet 9 of 10 Earth Reference Logic Schematic Sheet 10 Power Supplies Schematic 140 Sheet 1 of 1 Display and Keyboard Schematic TOP Side 33120-66521 REV a TOP Side 33120-66502 REV C Manual Part Number