Power/Inverter Board - AOC LM2028 Service Manual

8.2.3 POWER/INVERTER BOARD

1) No power
Check CN12 pin2, 4 = 12V
NG
Check AC line volt 110V or 220V
OK
Check the voltage of C905 (+)
OK
Check start voltage for the pin3 of IC901
OK
Check the auxiliary voltage is bigger than 10V and
smaller than 20V
OK
Check IC901 pin8 PWM wave
OK
Check Q901, R914, T901, D910, D901,R903
‚ ñ SN[¶ u 5~ ô O î • D e™ N u(
NG
NG
NG
NG
NG
QQ:505966338
Check AC input
Check bridge rectified circuit and F901 circuit
Check R906, R907, R929, C923 and Change IC901
1) Check IC901
2) Check D902, D904, C907 and OVP circuit
Check IC901
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AOC LM2028