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Haier L32Rl LCD TV power supply voltage is sent +5 V, +12 V and +24 V three groups , including 5V standby voltage , power supply to the motherboard standby circuits , 12V power supply to the motherboard , 24V power to the backlight .QQgservice manual download site
Power board working circuit diagram is shown below.
1 . Standby circuit during startup
Connected to the mains power supply board , 220V through C6, LF2, VR1, C3, C5, C4, LF1, Ll filter, then by BD1 rectification, Cl filtering, get +310 V DC , two routes were treated with Tl and T3 transformer primary add to V2 's "D" pole, standby power chip U3 (NCP1014AP65G) of ( 5 ) feet. Leaving aside aside the main power circuit , one that standby power chip U3 , U3 's ( 5 ) feet have power, the first chip built- start circuit to charge the E6 , E6 when the voltage rises to about 7.5V. U3 internal oscillation circuit starts to oscillate into operation , after U3 work in the primary auxiliary winding of the transformer T3 12V, 15V DC voltage of the two groups . 12V power supply providing secondary U3 work to maintain oscillation ; 15V connected transistor V9 (C1008) c pole. V9 by the on / off control circuit to achieve the main power supply control Ul . T3 generates +5 V/0.7A transformer secondary voltage control circuit to the motherboard ( keys, remote control signal processing , on / off processing circuit J supply.
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