Agilent Technologies 6621A, Service Manual

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LIST OF FIGURES
Figure Page
2-1
2-2
2-3
2-4
Outpot Board, Secondary Interface Circuits, Block Diagram………………………………………………………………………..2-9
2-5 Outpot Board, Power Mesh and Control Circuits, Block …………………………………………………………………………..2-12
2-6 Voltage and Current Control Circuits, Simplified Schematic ……………………………………………………………………2-13
2-7 Typical Output Range Characteristics ……………………………………………………………………………………………….2-15
2-8 Typical Downprogramming Characteristics Below 2.0 V …………………………………………………………………………2-16
2-9 Overvoltage Protection Circuits, Block Diagram ……………………………………………………………………………………2-18
3-1 Operating Ranges Available in Models 6621A-6624A and 6627A ………………………………………………………………….3-3
3-2 Current Monitoring Resistor Setup …………………………………………………………………………………………………….3-4
3-3 Basic Test Setup…………………………………………………………………………………………………………………………..3-5
3-4 Down Programming Speed Test Setup ………………………………………………………………………………………………..3-7
3-5 CV Down Programming Speed Test Waveforms …………………………………………………………………………………….3-7
3-6 CV UP Programming Speed Test Setup ……………………………………………………………………………………………….3-7
3-7 CV Up Programming Speed Test Waveforms………………………………………………………………………………………...3-8
3-8 Transient Recovery Time Test Setup …………………………………………………………………………………………………..3-9
3-9 Transient Response Waveform …………………………………………………………………………………………………………3-9
3-10 Fixed OV Protection Tea Setup …………………………………………………………………………………………………………3-9
3-11 OV External Trip Test Connections…………………………………………………………………………………………………...3-10
3-12 Negative Current Limit (-CC) Readback Accuracy …………………………………………………………………………………3-12
4-1
Agilent 6621A-6624A and 6627A Multiple Output Supplies, Assembly Locations ………………………………………………4-3
4-2
4-3
40WLV Output Board, Fuse and Test Point Locations …………………………………………………………………………….4-8
4-4 40WHV Output Board, Fuse end Test Point Locations……………………………………………………………………………..4-10
4-5 80WLV/80WHV Output Boards, Fuse and Test Point Locations ……………………………………………………………….4-11
4-6 Initial Troubleshooting and Board Isolation…………………………………………………………………………………………4-15
4-7
4-8
Signature Analysis Test Setup ………………………………………………………………………………………………………...4-19
4-9 Output Board Troubleshooting ……………………………………………………………………………………………………….4-31
4-10 Low Voltage Output Board Waveforms During Self Exercise Routine…………………………………………………………...4-37
4-11 High Voltage Output Board Waveforms During Self Exercise Routine…………………………………………………………..4-39
4-12 DAC Amplifier Circuit Troubleshooting …………………………………………………………………………………………….4-41
4-13 Overvoltage
Troubleshooting …………………………………………………………………………………………………………4-42
4-14 Output Held Low Troubleshooting…………………………………………………………………………………………………...4-44
4-15 Output Held High Troubleshooting ………………………………………………………………………………………………….4-47
4-16 OV Circuit Will Not Trip Troubleshooting …………………………………………………………………………………………..4-48
4-17 Signal Processor U327, Overvoltage Circuit, Schematic Simplified ……………………………………………………………….4-53
4-18
4-19 Signal Processor U327, Status Monitor Circuit, Simplified Schematic ……………………………………………………………4-57
iii
Agilent 6621A-6624 and 6627A Multiple Output Power Supplies, Block Diagram ………………………………………………2-2
Output Operating Ranges for Agilent Models 6621A-6624A and 6627A ………………………………………………………….2-3
4-20 Status Problems Troubleshooting ………………………………….………………………………………………………………...4-58
Signal Processor U327, Power-On/Start-Up Circuit, Schematic Simplified ……………………………………………………...4-53
GPIB Board, Block Diagram ……………………………………………………….…………………………………………………2-6
GPIB Board, Fuse and Test Point Locations ………………………………………………………………………………………….4-7
GPIB Board and Front Panel Troubleshooting ……………………………………………………………………………………..4-17
6-1 Power Distribution Schematic …………………………………………………………………………………………….……………6-5
6-2 GPIB Board, Component Location …...………………………………………………………………………………………………...6-7
6-2 GPIB Board, Schematic Diagram …………………………………………………………………………………………………….....6-8
6-3 Output 1 & 2 Board, Component Location ………………………………….………………………………………………………...6-9
6-3 Output 1 & 2 Board, Schematic Diagram …………………………………….……………………………………………………..6-10
6-4 Output 3 & 4 Board, Component Location ………………………………….……………………………………………………….6-15
6-4 Output 3 & 4 Board, Schematic Diagram …………………………………….…………………………………………………….6-16
6-5 Output 1 & 2 80W Board, Component Location …………………………….………………………………………………………6-25
6-5 Output 1 & 2 80W Board, Schematic Diagram ……………………………….……………………………………………………...6-26