Fluke 732B - Theory of Operation

4-1
Chapter 4
Theory of Operation
Title Page
4-1. Introduction ............................................................................................ 4-3
4-2. Overall Functional Description .............................................................. 4-3
4-3. Model 734A Functional Description ................................................. 4-5
4-4. Model 732B-7001 External Battery/Power Supply ........................... 4-5
4-5. 732B Circuit Description ....................................................................... 4-5
4-6. 10V Reference Circuit ....................................................................... 4-5
4-7. Generating the 1.018V Output....................................................... 4-7
4-8. Biasing the Refamp for Low Temperature Coefficient................. 4-7
4-9. Sense Current Cancellation ........................................................... 4-7
4-10. Buffering of the 10V Output ......................................................... 4-8
4-11. Oven Temperature Controller A4 ...................................................... 4-8
4-12. A1 Front Panel Assembly .................................................................. 4-8
4-13. Power Supplies and Battery Charger Assembly A5 .......................... 4-9
4-14. Overvoltage Protection Circuitry .................................................. 4-9
4-15. Raw DC Power Supply.................................................................. 4-11
4-16. Battery Charger.............................................................................. 4-11
4-17. +11.5V Preregulator ...................................................................... 4-11
4-18. +11.5V Low-Dropout Regulator ................................................... 4-12
4-19. -6V Power Supply.......................................................................... 4-12
4-20. IN CAL Logic................................................................................ 4-12
4-21. LED Drive Logic ........................................................................... 4-12
4-22. AC Power to Battery Power Switching Circuitry.......................... 4-13
4-23. Battery Circuit ............................................................................... 4-13
4-24. Rear Panel Connections................................................................. 4-13
4-25. Low-Battery Shutdown Circuitry .................................................. 4-14
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