IDE PCB burnt resistor/capacitor

I have this old IDE HDD that was sitting in a media enclosure [like an external HDD enclosure, but you can plug to the TV and play videos and images directly from it]

In my infinite stupidity, instead of using the original power adapter [it was lost in a box somewhere], I used another enclosure's adapter, thinking that since they were the same voltage and same plug type, it would work.

burn goes the hard drive [enclosure still works]

Upon inspection, I quickly find the burnt chip, which is located right next to the power plug of the HDD.




According to this forum's thread, that chip is to regulate/protect the input voltage. Hence, it's some sort of resistor, or breaker.

The chip is pretty big, there are only 2 solder points, so I know I can do that sort of soldering job [I've done smaller].

All I need is : what am I looking for as a replacement?

I know I don't need the exact same chip, I just want something to put there that will prevent the actual hard drive from frying.



a new PCB board on eBay for that HDD is 40$, which is the price of a newer, bigger hard drive. Since no data of value is on the HDD, I don't care to replace the whole board. I just want to try my luck at fixing this one.

can u get any numbers off of it?

Upon examination by the loupe, I could read this




The "ST" is in italic in a printed black case, so it seems like it's a brand
Upon googling, I found the manufacturer
http://www.st.com/stonline/
The logo matches


The G37 could also be 637, but more likely to be G37 since the loop part of the G isn't closed [like a 6 would be]

Or it could be G.37 [I can see a tiny little dot]

Upon re-examination

It is not G.37

It is b37 [there was a crack making it look like a 6 or G]

Im leaving again back towards

637


the thing is, the chip is cracked right through the middle of all that text.

The more I look at it, the more it looks like a 637.

But there's a weird crack that looks like a C in front of it, which would be a nice location, since the 637 is more to the right than the rest of the text.

but that C is one nasty C "looks a lot like a crack"

I compared the PCB to another hard drive's PCB. The other hard drive has a few big chips right next to the molex power plug and they are marked as capacitor.

I guess this helps narrow down since I can assume I'm looking for a capacitor and not a resistor.

Too bad they aren't marked as what kind of capacitor.

It's a DIODE

I just found out from further google searching.

Time to find the proper diode replacement