CONFIDENTIAL
5 Troubleshooting
CF21G*
5-7
5-1-13 V Size or Pos. Variation Failure
IC250 Pin 23 output varies with
different DAC values?
Yes
Check some parts around IC250.
Check bias voltage.
Check and replace IC250 and IC301.
No
5-1-14 High Voltage Failure
Q504 gate driving pulse exist?
The waveform is right?
Check +12 V line.
Check and replace
Q502, Q503, R511, IC501.
Yes
No
Done.
12
Are there some voltages
(350V, 30V, -210V, etc)
at secondary part of FBT?
Check and replace Q504, D508,
D509, D530, D507, D505.
Yes
No
WAVEFORMS
12
Q504, Gate
Summary of Contents for CF21G Series
Page 32: ...CONFIDENTIAL CF21G 6 1 6 Exploded View and Parts List ...
Page 33: ...Memo 6 Exploded View Parts List 6 2 CF21G CONFIDENTIAL ...
Page 61: ...CONFIDENTIAL Memo 8 Block Diagrams 8 2 CF21G ...
Page 63: ...Memo 9 Wiring Diagram 9 2 CF21G CONFIDENTIAL ...
Page 65: ...CONFIDENTIAL 10 Schematic Diagrams 10 2 CF21G 1 368 V IC601 1 ...