Fluke Car Amplifier 5725A Manual De Usuario
5725A
Instruction Manual
ii
4
Theory of Operation........................................................................... 4-1
4-1.
Introduction .......................................................................................... 4-3
4-2.
Overall Functional Description ............................................................ 4-3
4-3.
1100V AC Range Functional Description ....................................... 4-5
4-4.
11A Range Functional Description.................................................. 4-6
4-5.
Operation in the 11A DC Range.................................................. 4-7
4-6.
Operation in the 11A AC Range.................................................. 4-7
4-7.
Voltage and Current Standby Modes ............................................... 4-7
4-8.
Voltage Standby........................................................................... 4-7
4-9.
Current Standby ........................................................................... 4-7
4-10.
How the 5700A and 5725A Communicate ...................................... 4-8
4-11.
Description of the Out-Guard Lines (5725A Side) ..................... 4-8
4-12.
Description of the In-Guard Lines............................................... 4-9
4-13.
Functional Summaries by Assembly................................................ 4-10
4-14.
Detailed Circuit Description ................................................................ 4-11
4-15.
Interconnect Assembly (A1) ............................................................ 4-11
4-16.
Power Supply Assembly (A4).......................................................... 4-12
4-17.
High Voltage Supply Section ...................................................... 4-13
4-18.
Switching Section ........................................................................ 4-14
4-19.
Current-Limit Section.................................................................. 4-15
4-20.
System Supply Section ................................................................ 4-15
4-21.
Fan Supply Section ...................................................................... 4-16
4-22.
Digital Assembly (A5) ..................................................................... 4-16
4-23.
Microcomputer ............................................................................ 4-16
4-24.
External RAM.............................................................................. 4-16
4-25.
External ROM.............................................................................. 4-16
4-26.
EEROM ....................................................................................... 4-18
4-27.
Data Latch.................................................................................... 4-18
4-28.
Strobe Lines ................................................................................. 4-18
4-29.
Led Driver.................................................................................... 4-18
4-30.
Optoisolator Link......................................................................... 4-18
4-31.
Break-Detect Circuitry................................................................. 4-19
4-32.
Power Up and Reset Circuitry ..................................................... 4-19
4-33.
Watchdog Timer .......................................................................... 4-19
4-34.
Current Amplifier Assembly (A2) ................................................... 4-19
4-35.
Error Amplifier Section ............................................................... 4-21
4-36.
Output Stage Section ................................................................... 4-22
4-37.
Monitor Section ........................................................................... 4-22
4-38.
Control and Switching Section .................................................... 4-23
4-39.
Power Supply Section.................................................................. 4-23
4-40.
High Voltage Amplifier (A3)........................................................... 4-24
4-41.
Input Amplifier ............................................................................ 4-24
4-42.
Integrator...................................................................................... 4-26
4-43.
Window Comparator ................................................................... 4-26
4-44.
Input Clamp ................................................................................. 4-26
4-45.
Transconductance and Cascode Stage......................................... 4-27
4-46.
Midstage ...................................................................................... 4-27
4-47.
Midstage -400V Filter ................................................................. 4-27
4-48.
High Voltage Heat Sink Assemblies ........................................... 4-27
4-49.
Autobias Current Source ............................................................. 4-28
4-50.
Autobias Sense Circuit ................................................................ 4-28
4-51.
High Voltage Amplifier Feedback............................................... 4-29
4-52.
Signal Transformers .................................................................... 4-29
4-53.
Temperature Monitoring.............................................................. 4-29