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Old 11-20-2011, 10:59 AM   #17
Huttonfrank
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Join Date: Nov 2011
Posts: 1
Default Re: Philips LCD TV with Sound, No Picture (model 42PFL5322/10)

I am trying to repair a LG 32LC56. It has a single inverter board very similar to this one. (mine is VIT71020.66 MODULE INVERTER V.32 LCD-TV REF : 19.31T03.001) There are only six CCFLs. I have established that Philips and LG have a lot of common parts.
Symptoms are the same. On the inverter board is an IC type OZ964. The data sheet is free on the net. It is a DC/AC CCFL generator and control IC.
The application circuit shown is only for 1 CCFL so in this case the circuitry is much more extensive. I found that pin 3 of the OZ964 which is the enable pin goes from 5V when the backlight is on to 0v when it goes off. the line from the pin goes to various other points on the board, so it seems that an over or under voltage or current detection circuit is driving this line low and shutting down the CCFLs.
One of the transformer secondaries is 732 ohms, whereas the other 5 are 767 - 782 ohms. So there may be short circuit turns on this one. BUT even if I can prove it is the fault where could I get a replacement?
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