Fluke 5790A Service Manual page 4

5790A
Service Manual
2-17. Digital Section Detailed Circuit Description ........................................ 2-12
2-18. Digital Power Supply Assembly (A19) ............................................ 2-12
2-19. 5 V Power Supply ...................................................................... 2-12
2-20. 12 V Power Supplies.................................................................. 2-12
2-21. 35 V Power Supply .................................................................... 2-13
2-22. 75 V Power Supply .................................................................... 2-13
2-23. 35 V and 75 V Shut-Down Circuit .......................................... 2-13
2-24. CPU Assembly (A20)....................................................................... 2-14
2-25. Power-Up and Reset Circuit......................................................... 2-14
2-26. Clock Generation ......................................................................... 2-17
2-27. Watchdog Timer .......................................................................... 2-17
2-28. Address Decoding and DTACK (Data Acknowledge) ................ 2-18
2-29. Interrupt Controller ...................................................................... 2-19
2-30. Glue Logic.................................................................................... 2-19
2-31. RAM (Random-Access Memory) ................................................ 2-19
2-32. ROM (Read-Only Memory)......................................................... 2-19
2-33. Electrically-Erasable Programmable Read-Only Memory
(EEPROM)................................................................................... 2-20
2-34. DUART (Dual Universal Asynchronous Receiver/Transmitter)
Circuit........................................................................................... 2-20
2-35. Clock/Calendar Circuit................................................................. 2-20
2-36. Clock Filter Circuit ...................................................................... 2-20
2-37. CPU to Rear Panel Interface ........................................................ 2-20
2-38. CPU to Front Panel Interface ....................................................... 2-21
2-39. Front Panel Assembly (A2) .............................................................. 2-21
2-40. Clock Regeneration Circuitry ...................................................... 2-21
2-41. Refresh Failure Deject Circuitry .................................................. 2-21
2-42. Decoding and Timing Circuitry ................................................... 2-22
2-43. Control Display Circuitry............................................................. 2-22
2-44. Measurement Display Circuitry ................................................... 2-23
2-45. Keyboard Scanner Circuitry......................................................... 2-24
2-46. LED Circuitry .............................................................................. 2-24
2-47. Keyboard Assembly (A1)................................................................. 2-25
2-48. Analog Section Detailed Circuit Description ....................................... 2-26
2-49. Filter Assembly (A18)...................................................................... 2-26
2-50. Unregulated CH Supplies............................................................. 2-27
2-51. Unregulated LH Supplies............................................................. 2-27
2-52. Unregulated 17 SR Supplies ...................................................... 2-27
2-53. Triac Circuit ................................................................................. 2-27
2-54. FR1 Supplies ................................................................................ 2-27
2-55. Unregulated FR1 Supply.............................................................. 2-28
2-56. FR2 Supplies ................................................................................ 2-28
2-57. Regulator/Guard Crossing Assembly (A17)..................................... 2-28
2-58. Voltage Regulator Circuitry......................................................... 2-28
2-59. Regulated LH Supplies ................................................................ 2-29
2-60. Regulated 17 S Supplies ............................................................ 2-29
2-61. Regulated 15 CH Supplies ......................................................... 2-29
2-62. FR1 Supply .................................................................................. 2-29
2-63. FR2 Supply .................................................................................. 2-30
2-64. Guarded Digital Control Circuitry ............................................... 2-30
2-74. Transfer Assembly (A10) ................................................................. 2-33
2-75. Input Signal Paths ........................................................................ 2-33
2-80. Precision Amplifiers..................................................................... 2-35
2-81. Thermal Sensor Circuit ................................................................ 2-36
2-82. Digital Interface and Control ....................................................... 2-36
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