Re: Samsung BN44-00505A(PD23A0Q) psu, smd transistor types
As I indicate thee board in question does not have PFC, but you still have SMPS circuit that will still generated the back EMF by that power transformer, please read up on when happen when energize and deenergize inductor then you will understand why they put in the 1000V higher cap in that section. That cap is exposed to much higher that 330vdc.
http://i.stack.imgur.com/REXp2.png look at c12 which has the same function as CM804 of your power supply board.
http://electronics.stackexchange.com...details/254675
https://cdn.badcaps-static.com/pdfs/...4fc807c47b.pdf
See page 13, (F) = Voltage across the MOSFET Q1
BTW, common failure mode of ceramic cap is shorted circuit.
As I indicate thee board in question does not have PFC, but you still have SMPS circuit that will still generated the back EMF by that power transformer, please read up on when happen when energize and deenergize inductor then you will understand why they put in the 1000V higher cap in that section. That cap is exposed to much higher that 330vdc.
http://i.stack.imgur.com/REXp2.png look at c12 which has the same function as CM804 of your power supply board.
http://electronics.stackexchange.com...details/254675
https://cdn.badcaps-static.com/pdfs/...4fc807c47b.pdf
See page 13, (F) = Voltage across the MOSFET Q1
BTW, common failure mode of ceramic cap is shorted circuit.
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