Theory Of Operation - Fluke 867B Service Manual

2-1. Introduction............................................................................................. 2-3
2-2. Start-Up Sequence .............................................................................. 2-3
2-3. Function Selection .............................................................................. 2-3
2-4. Power Supply .......................................................................................... 2-4
2-5. Power Supply Input Voltages ............................................................. 2-4
2-6. Power Supply Output Voltages and Currents..................................... 2-6
2-7. Power Supply Signals ......................................................................... 2-7
2-8. Power ON/OFF Requirements............................................................ 2-8
2-9. NiCd Charging Requirements............................................................. 2-8
2-10. Battery and Line Level Detection....................................................... 2-8
2-11. Power Supply Functional Blocks............................................................ 2-9
2-12. Input Power Selector (A) .................................................................... 2-9
2-13. Boost Preregulator (B)........................................................................ 2-10
2-14. Battery Charger (C) ............................................................................ 2-10
2-15. DC-DC Converter (D) ........................................................................ 2-12
2-16. Backlight Current Sink (E) ................................................................. 2-12
2-17. Power Switch Circuitry (F)................................................................. 2-12
2-18. LCD Contrast Control (G) .................................................................. 2-12
2-19. Power-On Reset Circuit (H) ............................................................... 2-12
2-20. Linear Post Regulators (I)................................................................... 2-13
2-21. Input Overload Protection....................................................................... 2-13
2-22. Volt/Ohms Input Protection................................................................ 2-13
2-23. External Trigger and Logic Activity Input Protection........................ 2-14
Amps / mA / µA Input Protection....................................................... 2-14
2-24.
2-25. Input Signal Conditioning....................................................................... 2-14
2-26. AC Volts ............................................................................................. 2-14
2-27. DC Volts ............................................................................................. 2-16
2-28. mV DC................................................................................................ 2-16
2-29. Ohms................................................................................................... 2-17
2-30. Diode Test........................................................................................... 2-17
2-31. Capacitance......................................................................................... 2-17
2-32. mA/µA ................................................................................................ 2-18
2-33. Amps................................................................................................... 2-18
2-34. Waveform Processing ............................................................................. 2-19
2-35. Overview............................................................................................. 2-19
2-36. Detailed Description ........................................................................... 2-19

Theory of Operation

Title
Chapter 2
Page
2-1