HP 6033A series Service Manual page 6

Signature Analysis .............................................................................................................................................................. 41
Primary SA ..................................................................................................................................................................... 41
Front Panel SA................................................................................................................................................................ 41
Secondary SA ................................................................................................................................................................. 42
Power Section Troubleshooting.......................................................................................................................................... 47
Main Troubleshooting Setup .......................................................................................................................................... 48
Troubleshooting No-Output Failures .............................................................................................................................. 49
Power Section Blocks ..................................................................................................................................................... 50
Troubleshooting AC-Turn-On Circuits........................................................................................................................... 53
Troubleshooting DC-To-DC Converter .......................................................................................................................... 53
Troubleshooting Bias Supplies ....................................................................................................................................... 54
Troubleshooting Down Programmer .............................................................................................................................. 57
Troubleshooting CV Circuit ........................................................................................................................................... 58
Troubleshooting CC Circuit............................................................................................................................................ 58
Troubleshooting OVP Circuit......................................................................................................................................... 59
Troubleshooting PWM & Clock..................................................................................................................................... 59
Principles of Operation ........................................................................................................................................................ 61
Introduction ........................................................................................................................................................................ 61
HP-IB Board....................................................................................................................................................................... 61
Primary Microprocessor ................................................................................................................................................. 61
Address Switches........................................................................................................................................................... 61
EEPROM........................................................................................................................................................................ 63
Isolation .......................................................................................................................................................................... 63
Secondary Microprocessor ............................................................................................................................................. 63
Digital-to-Analog Converters ......................................................................................................................................... 63
Analog Multiplexer......................................................................................................................................................... 63
Status Inputs ................................................................................................................................................................... 63
Front Panel Board............................................................................................................................................................... 64
Address Latches and Decoders ....................................................................................................................................... 64
Volts and Amps Output Ports and Displays.................................................................................................................... 64
RPG and Latches ............................................................................................................................................................ 64
Front-Panel Switches and Input Port .............................................................................................................................. 64
Mode Indicators.............................................................................................................................................................. 66
OVP Adjust Control ....................................................................................................................................................... 66
Power Clear .................................................................................................................................................................... 66
Power Mesh and Control Board.......................................................................................................................................... 66
Overview ........................................................................................................................................................................ 66
AC Turn-On Circuits ...................................................................................................................................................... 68
DC-to-DC Converter....................................................................................................................................................... 68
Down Programmer.......................................................................................................................................................... 69
Bleeder Circuit (6038A only) ......................................................................................................................................... 69
Constant-Voltage (CV) Circuit ....................................................................................................................................... 69
Constant-Current (CC) Circuit........................................................................................................................................ 70
Overvoltage Protection (OVP) Circuit............................................................................................................................ 70
Power-Limit Comparator ................................................................................................................................................ 70
Control-Voltage Comparator .......................................................................................................................................... 70
Initial-Ramp Circuit........................................................................................................................................................ 71
Pulse-Width Modulator (PWM) ..................................................................................................................................... 71
Bias Voltage Detector..................................................................................................................................................... 71
AC-Surge-&-Dropout Detector....................................................................................................................................... 71
1-Second-Delay Circuit .................................................................................................................................................. 72
Replaceable Parts ................................................................................................................................................................. 73
Introduction ........................................................................................................................................................................ 73
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