Wanted Hitachi PCB

[andy50337]

Hi
I am looking for a replacement pcb for a hitachi 1tb hard drive model number HDT721010SLA360 the number of the board is 0A29989 BA3129 Mzh918 W3W6 If anyone can supply this please contact me at andyslowther@hotmail.com

Many thanks
Andy

[pcimage]

What's the problem with the drive?

[andy50337]

I connected the wrong power supply to the drive. I have already tried it in another enclosure and it does not work.

[fzabkar]

The usual culprit (12V TVS diode) is identified in this photo:
http://www.media-itservices.com/burned1.jpg

If your diode is shorted, then remove it with flush cutters. The drive will work without it, but it will no longer have overvoltage protection on the +12V supply. The other large diode is the 5V TVS diode. You can replace the 12V TVS with an SMBJ12A, and the 5V TVS with an SMAJ5.0A. Farnell UK should stock both.

[andy50337]

Hi
Thanks for the info which one should I try removing first and Wii it work with both removed or do I need to replace them?
Thanks

[fzabkar]

Get hold of a digital multimeter (US$10). Set in on the 200 ohms range and measure the resistances of each diode. If either diode measures close to 0 ohms, then remove it, otherwise leave it alone. You only need to replace the diode if you can't guarantee that you won't repeat your mistake.

[networkpc3000]

hi,
i have this PCB in stock. please feel free to contact me if need. also i saw your PCB look D3 has been burned. check it! if so just remove it.

[andy50337]

Hi
What would be the effects of fitting a board with a different firmware chip ?
Thanks

[fzabkar]

I'm not a DR guy, but AIUI there is the risk that fitting a non-native PCB could cause the NVRAM to be rewritten, thereby corrupting both the patient and donor.

NVRAM and NVRAM Repair:
http://www.datarecoverytools.co.uk/2009 ... am-repair/

[andy50337]

Thanks for the info guy's I have got a multi meter and will check the diodes when I get home from work.

[andy50337]

I have just measured the resistance of the diodes and d3 is 0.9 ohms and d4 is open circuit. I have allso measured the voltage coming out of my usb adaptor and the red wire reads 4.9v and the yellow 12.7. Is it safe to remove d3 and give it a try or should I replace d3 before trying.
Thanks
Andy

[fzabkar]

I have just measured the resistance of the diodes and d3 is 0.9 ohms and d4 is open circuit. I have allso measured the voltage coming out of my usb adaptor and the red wire reads 4.9v and the yellow 12.7. Is it safe to remove d3 and give it a try or should I replace d3 before trying.

Yes, that should be safe.

[pcimage]

I have just measured the resistance of the diodes and d3 is 0.9 ohms and d4 is open circuit. I have allso measured the voltage coming out of my usb adaptor and the red wire reads 4.9v and the yellow 12.7. Is it safe to remove d3 and give it a try or should I replace d3 before trying.
Thanks
Andy

Yes, it's worth a shot. Ideally you should replace D3 as a safety option, but if the drive doesn't start up immediately then cut the power right away.

[andy50337]

Hi all
Latest update I removed 12 v diode double checked voltage and gave it a try, the drive spun up but faster than I've ever heard one spin before so I unplugged. Looks like new pcb is needed. Thanks again for all the help.

[Eric Lee]

Hi, I have this working PCB, pls let me know when you need it.

Thanks, Eric