ATX Power Supply - What is this burnt up thing inside?

[DTeCH]

Hey dudes :)

I opened up my power supply, & found the fuse intact, & brand new looking (really clean). Next, i checked for swollen capacitors, but none were found. Next, I held the board up to my face, & sniffed for that dead rat smell of burnt chips, & got a good nose full of it.

Decided to look closer, & found in the shadows of the two big heat-sinks, a thingy with half of it's black shell gone, showing it's bare metalics inside. The thing was about an inch away from the fuse, & where the input power leads are soldered to the board.

My issue is identifying what the heck it is. Google is no help, it just confuses me. there are Op-amps, Power ICs, AC DC Converters, & Offline Switchers that apparently look like it, but that does not help one bit.

It looks like this image ( 7 pins, not 8 ):


Based on where it is on the board, & what board it is in (PC ATX Power Supply), I'm hoping for an educated guess with explanation on why it seems to be that.

Any help is greatly appreciated as always. :)

[Joseph Martell]

The type of form factor you are describing is a DIP-7. DIP = Dual In-line Package. 7 is for how many pins are on the package.

This is going to be pretty difficult since identifying these ICs is mostly done by the markings on the top of the package. Based on your description it sounds like that is not an option.

Often circuit board manufacturers will have a component designation printed on the actual circuit board. Check near the IC for any visible number/letter combinations. This may help identify what that part was.

What is the exact manufacturer and part number of the power supply? If someone has the same one then you may be able to do a side-by-side comparison via photos.

Finally, you could identify the rest of the components that the IC was connected to and draw out a schematic. If you know more about how it fits into the overall circuit then you might be able to figure out the purpose of the component and thus a suitable replacement.

[Stewart Ross]

PC power supplies are usually replaced when they fail; it is not economical to perform board-level replacement of components on a power supply that can in general be purchased fairly cheaply. The old PSU is easy to swap out.

If one small chip has been destroyed in your PSU there are most likely to be other failed components which are less obvious but just as dud as the burnt-out 7-pin DIP. Switched-mode power supplies are efficient but if they fail such failures may well be catastrophic (i.e. involving multiple components in a domino-chain of failures) and terminal.

I have had to replace several PSUs over the years, and would advise you to look for a compatible PSU instead of trying to fix the one you have got.

-Stewart

[DTeCH]

Hello Joseph :)

Thanks you for your info.

The Power Supply model is "Ultra X4 ATX 500w Modular Power Supply" (model # ULT-HE520X), & before completing the post of this question/topic, I browsed all over google, but only found it on eBay with a less than optimal picture.

The flow of the wiring seems to be: Main leads -> fuse -> Big Capacitor at rear side of the board -> Back to the 2 Diodes at the location of the fuse again -> either the IC in question, or the little transformer behind it.

It seems to have something to do with dealing with the main power from the wall after being passed through the fuse, & main Capacitor. I could be off a little here, but it is basically in that order to my eyes.

Yes, the shell of the little chip was no longer readable due to not even being on it any longer.

A side-by-side comparison would be nice in this situation, but this PSU was top of the line when I got it, & despite having an expected price tag that's considered cheap to most, is NOT cheap to me. I live in the Cayman Islands, & NOTHING is cheap here... also, there are no Radio Shacks, or Circuit Cities anywhere.

I have a few old power supplies laying around, & was hoping to be able to simply swap out a few parts, but the old ones are not modular, nor are they PCI-E ready.

Thanks for your response, & I'm sure this maybe a difficult one to solve, but any, & all replies are better than none at all. :)

[DTeCH]

Hello Stewart :)

I live in the Cayman Islands, & this is more of a curse, than blessing. This place is overly expensive. Gas prices are now US$1.90 per gallon in the US, but still US$7+ here. This is a very unfair, & unforgiving place.

The PSU may have a price tag of...say US$80.00 in the US, but here, that price more than 5 times itself. A simple little PSU, yet cost more than a months US rent. What's worst is the cost of the little part. it maybe US$1 to US$5, but to get it here is another story.

This place is Bank Crazy... all about profit. A simple way of fixing something MUST be explored here, otherwise we'll go bankrupt. :)


Just another example so I'm clear...

A house in the US costs around, say... US $40,000. Here, that price buys NOTHING. Not even the land for the location of a small house. Here, a little tiny bit of land that's just a few feet x a few feet cost a bare minimum of US $130,000... without an actual house on it. A crappy 1 bed 1 bath home costs well over a half a mil, & if you want brand new, well over 1 mil US$.

Not fair here at all. Minimum wage is below $5 bucks an hour.

A person here would be crazy not to attempt a quick fix before running off to the store to pay a month's salary on a silly PSU. lol

If it was any other place, I would absolutely agree with you on the simplicity of replacement, but this place is NUTS + TAX. :)

[Stewart Ross]

I do understand the high costs where you are, but there really is no simple fix possible. Without a schematic for that PSU there is no way of knowing what the destroyed component was, or of identifying any others that have been damaged. Replacement is really the only option.

-Stewart