This nice 1920x1200 monitor has dead backlight. Image correctly formed on LCD but no backlight. His owner says that last days it was working it got unusually hot in the lower side.
Once opened, I detect a short mosfet (540N ?) and a short diode, plus a perforated IC [U0815] (cannot read its name as the perforation is precisely there). I don't have schematics (Apple service manual considers that nobody will repair it at component level) but I assume that [U0815] is a controller for 3 power LED drivers, one for each LED strip at the panel (LCD panel LM240WU6(SD)(A1), with 3 LED strips). Shorted mosfet and diode belong to a single power driver circuit.
I attach image with interesting spots. Damaged driver circuit is the middle one (transistor disconnected and diode already stripped).
Since [U0815] is irreplaceable to me, I'm forced to replace logic board, BUT, I'm afraid that there's something at middle LED strip that caused this failure to the driver and controller, so changing logic board would be a poor long term investment...
And then the question: how can I cheaply test each LED strip to be sure that they're OK before buying a new board? According to panel datasheet each strip needs about 60V and 350mA.
Update: after finding this identical case, I get to know that controller is a HV9982. He doesn't explain if the repair was successful. Actually, he didn't even say that he was repairing this kind of monitor!
Once opened, I detect a short mosfet (540N ?) and a short diode, plus a perforated IC [U0815] (cannot read its name as the perforation is precisely there). I don't have schematics (Apple service manual considers that nobody will repair it at component level) but I assume that [U0815] is a controller for 3 power LED drivers, one for each LED strip at the panel (LCD panel LM240WU6(SD)(A1), with 3 LED strips). Shorted mosfet and diode belong to a single power driver circuit.
I attach image with interesting spots. Damaged driver circuit is the middle one (transistor disconnected and diode already stripped).
Since [U0815] is irreplaceable to me, I'm forced to replace logic board, BUT, I'm afraid that there's something at middle LED strip that caused this failure to the driver and controller, so changing logic board would be a poor long term investment...
And then the question: how can I cheaply test each LED strip to be sure that they're OK before buying a new board? According to panel datasheet each strip needs about 60V and 350mA.
Update: after finding this identical case, I get to know that controller is a HV9982. He doesn't explain if the repair was successful. Actually, he didn't even say that he was repairing this kind of monitor!
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