Fried Smooth L7251 controller, possibly fried board WD 750GB

[Dmitri]

Here are the xrays...

Aaaahhhh, Friday!...

Attachments

PLAYBOT FRIDAY @ HDDGURU!

[SecretRaindrop]

We have a Nordson Dage XD7600NT.
Heres a link:
http://www.nordson.com/en-us/divisions/ ... amond.aspx
I got the board yesterday thanks to a wonderful member of this community offering to send me one from sweden
So today i used a hot air blower to remove the U12 and sodder it on the new board:
http://imgur.com/mlCD6pF
http://imgur.com/fBTGxvD
Should try connecting it to the hdd and see if it works here on my work computer, or take it home in case it only powers up once?

[SecretRaindrop]

Bad news guys...
I got home and plugged in the hdd, it zapped again.
I dont have the tools to see if it was the Smooth controller that burned up, so ill update you on that tomorrow.

[ShaneWard]

looks like the pre-amp in the drive has been shorted and killed the new board. Looks like it will need to be a head swap...
#
Shane

[data-medics]

I will never understand people like this original poster, who'd rather spend weeks replacing components to try and repair a PCB when you only have to move one chip over to a new board and be done with it.

Makes no sense to me.

[data-medics]

I highly doubt that it's the preamp frying the PCB. I'd say it's most likely your power supply, or possibly the motor.

[pcimage]

I will never understand people like this original poster, who'd rather spend weeks replacing components to try and repair a PCB when you only have to move one chip over to a new board and be done with it.

Makes no sense to me.

I think he has done just that, moved U12 to another board.

[SecretRaindrop]

I did end up just moving U12, but replacing all the parts would have been great practice for me, i work with this daily as a trainee, and it interests me
Im guessing its the motor, as i have never had any issues with the power supply, and it is currently running my system without any hiccups.

[fzabkar]

The damage to the original PCB is consistent with a preamp failure, not a motor problem.

It's a pity your PCB photos aren't anywhere near as good as your X-rays. However, if you can provide a better quality image, I can show you the voltage test points.

After we have confirmed whether these voltages are OK, you could then try powering up the board on its own. If all is still OK, then we could isolate the drive's HDA contacts with a business card and try powering up the board on the drive.

Alternatively we could test the preamp's negative supply for a short circuit, with the PCB both on and off the drive.

[mr_spokk]

I vote for preamp in this case, and if you need help with your drive you know where to find me

Cheers/ Bosse

[mr_spokk]

I think he has done just that, moved U12 to another board.

Yep, I sent him a known working board.

[SecretRaindrop]

I will bring the drive back to work tomorrow and see if i can get some more detailed pictures
I have another board coming from Hong Kong, that i was planning on sending to mr_spokk.
If its ok i can just pay you for this card and use the one from hong kong to try again?
fzabkar, i am pretty sure the new board that i tried today is dead, as i could see smoke and hear it short out when i turned the computer on...
Will have to wait for the board from Hong Kong to try your suggested methods

[SecretRaindrop]

The board fried on the smooth chip and the exact same place.
I have taken some better pictures:
http://i.imgur.com/Im7PhaG.jpg
http://i.imgur.com/BMQFBLx.jpg
http://i.imgur.com/ZkU11Qg.jpg
http://i.imgur.com/qFNtNAy.jpg
If you want even better pictures i have a better camera at home with a macro lens
As i have said before i am not sure if i want to try to change the head and preamp, as it probably isnt very easy (need a very clean room) and the parts are probably expensive; only assuming things, please correct me if im wrong.

[jerovsek]

send drive to mr_spokk or some other PRO DR
better then testing without good knowledge

[fzabkar]

ISTM that the new board has sustained the same overvoltage on the 5V input.

Did you check D3 and R67?

Did you measure the voltages at the SATA plug?

[SecretRaindrop]

I dont have important enough data that i want to pay hundreds of dollars/euroes/thousands of NOK to get the data back
R67 is 57 Ohm.
D3 is shorted.
The sata plug should be working correctly, it has a pump and a fan running of it now (i know they arent as sensitive to fluctuations/overvoltages) and the other drive (2TB seagate) ran fine of that same power/plug.

[fzabkar]

Your PSU is killing your PCBs.

[SecretRaindrop]

hmm, okay, i will try the next pcb with my work computer

[SecretRaindrop]

Happy new Year!
I got the new PCB, and transferred the U12.
This time i connected the drive to my work computer, and it didnt fry the smooth controller, so i guess my psu needs to be changed...

But the computer isnt seeing the drive either, and is doesent spin up when the computer boots.
The PCB gets hot, but not the kind of everything is frying itself hot ^^

[fzabkar]

Assuming that U12 was transferred correctly, then I expect that your preamp may be dead. Does the drive spin up if you place a business card between the PCB and the J1 contacts?

Unfortunately it appears that you are one of many victims of WD's bad designs. Ironically, if the fusible zero-ohm resistors (R64 and R67) had been replaced with wire links or blobs of solder, then your data would now be recoverable simply by removing a shorted TVS diode. However, because of WD's absurd design, these "fuses" not only do not protect your data, they are in fact responsible for your data loss.