eagle1109
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Hello,
I'm trying to fix this Dell 255W PSU, I think the fuse was broken and I replaced it, then I tried to power up the unit but didn't work on output rails.
So, I measured the voltage on the high power side and I think the power MOSFET isn't working, the drain receives 316V from the high voltage capacitor, the gate is 8.3V from the switcher IC and on the source I found 8.3V, so I thought the MOSFET is broken.
Is my guess right?
![DellPSUProblem.jpg DellPSUProblem.jpg](https://www.edaboard.com/data/attachments/76/76749-0f8bddd027d7ff79abc7fdba2634d850.jpg)
I'm trying to fix this Dell 255W PSU, I think the fuse was broken and I replaced it, then I tried to power up the unit but didn't work on output rails.
So, I measured the voltage on the high power side and I think the power MOSFET isn't working, the drain receives 316V from the high voltage capacitor, the gate is 8.3V from the switcher IC and on the source I found 8.3V, so I thought the MOSFET is broken.
Is my guess right?
![DellPSUProblem.jpg DellPSUProblem.jpg](https://www.edaboard.com/data/attachments/76/76749-0f8bddd027d7ff79abc7fdba2634d850.jpg)