Fluke 5790A Service Manual page 32

5790A
Service Manual
2-2
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
2-83. A/D Amplifier Assembly (A15) ....................................................... 2-37
2-84. Chopper Circuit............................................................................ 2-37
2-90. A/D Amplifier Circuits ................................................................ 2-39
2-96. Digital Control and Power Supply ............................................... 2-41
2-97. DAC Assembly (A16) ...................................................................... 2-41
2-98. DAC Assembly Reference Circuitry............................................ 2-42
2-99. Duty-Cycle Control Circuit.......................................................... 2-43
2-100. DAC Filter Circuit ....................................................................... 2-44
2-101. DAC Output Stage ....................................................................... 2-44
2-102. Sense Current Cancellation Circuit .............................................. 2-44
2-103. Linearity Control Circuit.............................................................. 2-44
2-104. Negative Offset Circuit ................................................................ 2-45
2-105. Wideband Module (A6, Option -03) ................................................ 2-45
2-106. Input Signal Path for the Upper Four Ranges .............................. 2-47
2-107. Input Signal Path for the Lower Four Ranges.............................. 2-47
2-108. DC Offset Feedback for Amplifier U3 (Lower Ranges).............. 2-48
2-109. RMS Sensor Circuit ..................................................................... 2-48
2-110. Transfer Methodology.................................................................. 2-48