AOC LM2028
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8.2.3 POWER/INVERTER BOARD
1) No power
Check CN12 pin2, 4 = 12V
NG
Check AC line volt 110V or 220V
Check AC input
Check the voltage of C905 (+)
Check bridge rectified circuit and F901 circuit
Check start voltage for the pin3 of IC901
Check R906, R907, R929, C923 and Change IC901
NG
Check the auxiliary voltage is bigger than 10V and
smaller than 20V
1) Check IC901
2) Check D90
2
, D90
4
, C907 and OVP circuit
OK
OK
OK
NG
NG
NG
Check Q901, R914, T901, D910, D901,R903
OK
Check IC901 pin8 PWM wave
OK
Check IC901
NG
英华家电维修资料专用 QQ:505966338
