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Electronics => Repair => Topic started by: Ropterex on March 16, 2020, 03:22:53 pm

Title: Diode replacement
Post by: Ropterex on March 16, 2020, 03:22:53 pm
Hi! yesterday I had mi PC's power supply blow up on me, upon some inspection I found a broken diode inside (stpsc606d). Its the first time im trying to fix something like this, so I have a few questions maybe someone can help me with:

1. the power supply is about 6 years old, could it be that de diode blew up on its own? or is this just a sign of a deeper issue. Could it have been a power surge? (I didnt have any surge protection at the time)

2. Im from Argentina, so I can't finde this exact sane diode to replace it, is it posible to use something "more common" that I can actually buy here?

Thank you for your help! sorry for the bad english.
Title: Re: Diode replacement
Post by: TheMG on March 17, 2020, 12:57:41 am
That's a relatively low current but high voltage schottky diode, so I'm assuming it must be part of the PFC pre-regulator circuit?

If so, then it is highly likely there is a lot more wrong than just the diode. They do not usually blow apart like that for no reason, something else is probably shorted (likely the main switching transistors of the power supply) that caused grossly excessive current to flow through it.
Title: Re: Diode replacement
Post by: bob91343 on March 17, 2020, 03:46:20 am
Good answer, but my first guess is that the diode is rellatively cheap.  So I would take a chance and replace it to see if things start to work.
Title: Re: Diode replacement
Post by: james_s on March 17, 2020, 04:32:21 am
At the very least test the chopper transistor and any other semiconductors in the area. There's no point in wasting time replacing the diode only to have it blow up again from other parts being bad. 99.9% chance there are other faults.
Title: Re: Diode replacement
Post by: Ropterex on March 18, 2020, 02:10:00 am
Thank you for taking the time to answer!