– 7 –
KV-HF21M50/XF21M80
RM-952
6.
SELF-DIAGNOSTIC CIRCUIT
[+B overcurrent ªOCPº]
Occurs when an overcurrent on the +B(135) line is detected by Q604. If Q604 go to ON
and the voltage to pin 18 of IC301 should go down when V.SYNC is more than seven
verticals in a period, the unit will automatically turn off.
[Vertical deflection stopped]
Occurs when an absence of the vertical deflection pulse is detected by Q509 and IC001
shut down the power supply.
[Vertical deflection overcurrent]
Occurs when an overcurrent on V drive line is detected by Q507. Power supply will be
shut down when detect this by IC001.
[White balance failure]
If the RGB levels* do not balance or become low level within 5 seconds, this error will be
detected by IC301. TV will stay on, but there will be no picture.
* (Refers to the RGB levels of the AKB detection Ref pulse that detects IK.)
IC301
Y/CHROMA JUNGLE
FROM
CRT
FROM
[+B]
Q604 C
[V]
Q509/507
IC001
SYSTEM
IC003
MEMORY
B-DAT
IO-SDAT
IK-IN
MP/
PROTECT
IO-8DAT
O-LED
SDA
5
45
21
18
51
46
35
