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Thread: What components in PSUs fail first?

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    Default What components in PSUs fail first?

    What are the main reasons that a properly designed power supply fails?

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    What components in PSUs fail first?
    mosfet

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    Is it the MOSFETs fault, or is the transformer saturating, and so becoming a short?

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    Quote Originally Posted by rgbodosk View Post
    What are the main reasons that a properly designed power supply fails?
    Depends on the Layout, Design.

    These days it looks like its either the +5VSB Chip exploding or some other MOSFET (mostly in the aPFC Section).
    If a low quality Sleeve Bearing fan is used, its obviously the Fan as well.

    What is rarely the Issue are the Caps these days.

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    Quote Originally Posted by Stefan Payne View Post
    ...or some other MOSFET (mostly in the aPFC Section).
    Good to know it is the APFC MOSFET

    That was not at all clear from the article
    https://www.tomshardware.com/news/wh...sus,36712.html

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    Quote Originally Posted by ashiekh View Post
    Good to know it is the APFC MOSFET

    That was not at all clear from the article
    https://www.tomshardware.com/news/wh...sus,36712.html
    Naa, that's a primary switcher of a Leadex based unit.
    Those are rather shitty heatsinked for whatever reason...

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    Quote Originally Posted by Stefan Payne View Post
    Naa, that's a primary switcher of a Leadex based unit.
    Those are rather shitty heatsinked for whatever reason...
    Heatsinks are expensive, both the component and its contribution to final product weight (negatively affecting logistics).
    Careful what you wish for... You just might get it.

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    Quote Originally Posted by McSteel View Post
    Heatsinks are expensive, both the component and its contribution to final product weight (negatively affecting logistics).
    Yeah, but using an SMD Part and bolting a Heatsink next to it like you see on many modern units on the +12V Rectifying stage would possibly be better.

    On the other hand: If those FETs explode, you're lost, nothing you can do. If a TO-220 or 247 FET explode its salvagable.

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