I have a FSP 350W power supply from an Ahanix case. The primary stage on the +5VSB blew up, although it didn't blow the fuse.
Some parts got burned and crispy, more specifically, 2 1/8W resistors that are too burned to tell what their values were supposed to be.
I've attached a schematic of what the 5VSB primary circuits looks like (at least, to the best of my tracing and schematic drawing ability).
The orange X's indicates parts that were burned. Both transistors were shorted. R16 2.9ohm is a big resistor that went open circuit. The resistors I circled in red are the ones I can't ID.
R60 - tests open circuit. Not completely burned, but cooked to a nice golden brown. Bands are red-yellow-(purple or brown)-gold, so either 240ohm or 240M ohm. The third band is too darkened to tell for sure. I feel like it would see too much current when MOSFET is off to be 240ohms, so does it make sense to have a 240Mohm resistor there? It would make sense that it measures open-circuit because it's too high for my DMM.
"R1" - not really R1, but it didn't have a label on the PCB. Brown-blue-???-orange-gold. The ??? is a black, burned section. If no extra band, it could be 16k, but the burned section looks large enough it could have had an extra band there.
Any idea what those resistors should be? Also any guesses on what could have cooked those parts? All caps look fine.
Some parts got burned and crispy, more specifically, 2 1/8W resistors that are too burned to tell what their values were supposed to be.
I've attached a schematic of what the 5VSB primary circuits looks like (at least, to the best of my tracing and schematic drawing ability).
The orange X's indicates parts that were burned. Both transistors were shorted. R16 2.9ohm is a big resistor that went open circuit. The resistors I circled in red are the ones I can't ID.
R60 - tests open circuit. Not completely burned, but cooked to a nice golden brown. Bands are red-yellow-(purple or brown)-gold, so either 240ohm or 240M ohm. The third band is too darkened to tell for sure. I feel like it would see too much current when MOSFET is off to be 240ohms, so does it make sense to have a 240Mohm resistor there? It would make sense that it measures open-circuit because it's too high for my DMM.
"R1" - not really R1, but it didn't have a label on the PCB. Brown-blue-???-orange-gold. The ??? is a black, burned section. If no extra band, it could be 16k, but the burned section looks large enough it could have had an extra band there.
Any idea what those resistors should be? Also any guesses on what could have cooked those parts? All caps look fine.
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