I'm trying to repair my daughter's RCA television, and I need advice about choosing a replacement MOSFET. I've just ordered a 2SK2917 from Mouser to replace the 2SK2842 I pulled from the power supply. The current ratings are higher for the 2917, but my concern is the higher (but still small?) capacitance and inductance of this "larger" MOSFET. Will this be a problem?
FWIW, the 2842 I pulled from the board has higher current ratings than the 2SK2543 shown on the attached schematic. Probably means they knew this was under-specified?
I was lucky to find this schematic online, along with training materials, a troubleshooting guide and so on. It was soon obvious that the power supply is dead, and I removed TP020 (left side middle of schematic), the switching MOSFET for the transformer primary coil. It tested dead short. The info I found suggests replacing all the active components on the primary side if you find the MOSFET dead, so I've ordered all of the transistors and zeners. All cheap compared to the MOSFET.
FWIW, the 2842 I pulled from the board has higher current ratings than the 2SK2543 shown on the attached schematic. Probably means they knew this was under-specified?
I was lucky to find this schematic online, along with training materials, a troubleshooting guide and so on. It was soon obvious that the power supply is dead, and I removed TP020 (left side middle of schematic), the switching MOSFET for the transformer primary coil. It tested dead short. The info I found suggests replacing all the active components on the primary side if you find the MOSFET dead, so I've ordered all of the transistors and zeners. All cheap compared to the MOSFET.
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