Keithley 2002

Troubleshooting
2-8
Figure 2-2
Power supply block diagram
110/120VAC
IN
Fuse: F101
Power
Switch: S101
Power Transformer
T100
110/120V Switching
Q101, Q102, Q103, Q106
U102, U105
K101, K102
±15V Supply
CR113
C112, C113
U107, U109
Bootstrap Supply
CR114 - CR117
C116, C117
+5V Supply
CR112
C114, C115
U110
+15V
COM
-15V
+BS (34V to 38V)
Common 3
-BS (-34V to -38V)
+5V
Digital Common
Figure 2-3
Display board block diagram
Vacuum Fluorescent Display
DS901
Dot Drivers
U901, U905
Grid Drivers
U903, U904
Controller
U902
Key Matrix
S901 - S931
Reset
Tx
Rx