I bricked my Verbatim external hd when I accidentally used a 19V power supply (I could smell the
magic smoke).
The disk would not spin up. The power led was just emitting a short burst after pressing the power button.
I removed the disk from the enclosure and tried a diffrent USB>SATA board without success. After some research in the forums I discovered that the TVS might have sacrificed itself for the rest of the drive.
This site was also very helpful:
http://www.users.on.net/~fzabkar/HDD/TVS_diode_FAQ.htmlOne thing that was special for me that measuring the resistance of the TVS didn't yield unambiguous results (probably due to some capacitors in the circuitry).
I decided to press my luck and disconnect the TVS as suggested in some posts.
First I tried desoldering but I would have needed a lot more heat than I was comfortable to remove the TVS.
The next step involved pliers but (at least with the tools I had) I couldnt do it without applying major force to the pcb (and surrounding components) when the pliers slipped.
The final thing I tried was a dremel to cut the contact on one side of the TVS.
Now everything works again - sweet.
The hard drive was a Samsung HD204UI.
- Attachments
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- Full PCB
- pcb.JPG (130.06 KiB) Viewed 4918 times
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- The 12V TVS disconnected. The 5V TVS is undamaged.
- cuttvs.JPG (97 KiB) Viewed 4918 times