Barracuda XT, Barracuda, Barracuda Green, DiamondMax and other desktop SATA and IDE drives

[fzabkar]

I have identified the parts for you as best as I can:
http://www.users.on.net/~fzabkar/HDD/ST3500320AS/

A FETKY is a MOSFET and diode in a single package. I believe yours are manufactured by Fairchild, but I can't read the numbers.

I would power up the faulty board while it is disconnected from the drive. Measure the voltages at each of the regulators with respect to circuit ground.

A TVS (transient voltage suppression) diode is intended to clamp voltage spikes, and it also provides limited protection from sustained overvoltages, and reverse voltages.

What is a Silicon Transient Voltage Suppressor and how does it work?
http://www.vishay.com/docs/88436/appnote.pdf

Good luck.

[Railey505]

I'll send a clearer picture (FETKY, EEPROM) once I get back home this weekend.

1. Just want to know how sensitive is this EEPROM, is it safe to use a 20w-30w soldering Iron with a fine tip?

Regarding what you said:

 "I would power up the faulty board while it is disconnected from the drive. Measure the voltages at each of the regulators with respect to circuit ground"

2. which regulators (pins) and what exact voltages do I expect to get from them?

3. what would happen if ever I try first to replace the logic board without  transplanting the 8-pin serial EEPROM chip, will it erase/damage the existing Data inside my Hard Disk?

[fzabkar]

I use a temperature controlled soldering station.

Here are stories of failure and success (by a novice):
http://forum.hddguru.com/viewtopic.php?f=1&t=14945

My suggestion is to practice on a junk board before attempting the real thing.

Alternatively, ask your local TV/AV repair shop.

See this thread:
http://www.deadharddrive.com/forums/viewtopic.php?p=9531#9531

The OP writes that s/he "took the board to an electronics repair store and for $20 the ROM chip was swapped. "

I have identified the regulators in these photo clips:
http://www.users.on.net/~fzabkar/HDD/ST3500320AS/

Measure the +2.5V, -5.0V, and +1.2V test points. Be careful not to short anything with your probes. You must not damage the EEPROM.

[Railey505]

I've just powered up the faulty board while it is disconnected from the drive. Measure the voltages at each of the regulators with respect to circuit ground. See snapshoots (http://img526.imageshack.us/g/42952114.jpg/)
Notice that no reading on the test points for +1.2V Vcore for MCU and -5V, what would be the my next step, what component do I have to replace or do I need to change the whole PCB and transplant the EEPROM? How would I know if the EEPROM is still Okay?

[Grim0x]

@ Railey505

Im uncertain of the volatage measure points for this PCB, and the PCB's layout
in general.

But your EEPROM is more than likely going to be ok.
I would go as far as to say, there's a greater chance that your EEPROM is FINE,
as opposed to it being bad.

(PS - and you're sure your meter is working properly, and set to the right
reading?)
Do you get a reading after the TVS diode?
(if you dont know what that is - google HDD PCB TVS diode)





Sry Gents.

I only know of one person I could ask for such PCBs, I'll ask him
sometime next week, and let you know.
You should contact the person on this page: http://www.diytrade.com/china/4/products/5890770/hdd_pcb_for_seagate.html

They sell PCBs. I'm going to come here regularly and try to post contact info
for sources who sell such PCBs.

Here's another
http://www.alibaba.com/member/my102745988.html Contact here:
http://www.alibaba.com/member/my102745988/contactinfo.html

A bit of work for you
in this one (you have to pick a picture of your drive) http://hddpcbshop.com/
They say (at the bottom) that if you cant find it, they'll get back to you if
you leave a model number ect.

You could try contacting these people:
http://www.tradekorea.com/company-detail/C0075731/Shenzhen_Drivestar_Electronics_Limited.html
I cautiously mention that contact - for they claim to sell a PCB that will work for the "full range" of Seagate HDDs.
Saying it can be used for recovery/diagnosis ect. I havent heard of any such thing! (Fzkabar - have you?)

There is a possibility also, that a PCB of a DIFFERENT drive could work with yours... I'll fully investigate that notion before I state it as fact though.

Here's your PCB on ebay:
http://cgi.ebay.com/ST3500320AS-Barracuda-7200-11-HDD-PCB-Logic-Board-/220605635096?cmd=ViewItem&pt=...

[fzabkar]

I believe your most expedient solution would be a board swap. If the drive clicks with the new board, then you will need to transplant the EEPROM.

I believe the EEPROM is powered from the +2.5V supply, so it may have survived.

I'm not sure that I have chosen the correct test point for the -5V supply. I'd probe the pins in the 20-pin preamp connector nearby just to be sure.

In any case, the Vcore supply is either not working, or has been shut down for some legitimate (?) reason. Unfortunately I don't know enough about this drive to be able to take it much further. One final thing I would do would be to measure the load resistances on each supply with respect to ground. Do this with power disconnected.

[Railey505]

Thank Grim0x and fzabkar. I'm currently looking for a replacement board, what do I have to consider in searching for a replacement Logic board, except for the HD model: ST3500320AS, should it have the same P/N and Firmware? Regarding the measuring of the load resistances on each supply (kindly provide the location of each supply test points) with respect to ground, what would be the reading do I expect to see on each test points? Hoping you can still assist me in trouble shooting further the logic board.

[fzabkar]

I'm not a data recovery guy, but I would look for a PCB from a drive with SDxx firmware. The bulk of the firmware is actually stored on a firmware zone in the hidden System Area on the platters, not on the PCB. The PCB has a small amount of boot code in the EEPROM and MCU chips. However, any differences in boot code on the PCB will be accounted for when you transplant the serial EEPROM from patient to donor. The main MCU chip would have additional boot code in mask ROM, but I don't believe that it will affect the outcome in this case.

As for the supply test points, I was merely asking you to measure the resistances between ground and each of the +2.5V, +1.2V, and -5.0V test locations that I marked in my photo clips:

http://www.users.on.net/~fzabkar/HDD/ST3500320AS/

BTW, "circuit ground" can be any plated screw hole.

[Railey505]

Hi, just got someone selling a ST3500320AS unit with the following Details: (http://img230.imageshack.us/img230/7421/500gbforsalehd.jpg) Model: ST3500320AS P/N: 9BX154-303 Firmware: SD15 Date Code: 09173 Site Code: KRATSG Made in Thailand My SATA HD Details: (http://img63.imageshack.us/img63/6136/500gbmine.jpg) Model: ST3500320AS P/N: 9BX154-305 Firmware: SD1A Date Code: 09264 Site Code: WUXISG Made in China Firmware is SDxx But notice the last digit of the P/N is different. Please advice if i could use this as a donor for my HDA? Thanks

[Grim0x]

Hello again Raily.

Yes, I would considering the firmware family, that would be a good bet.

As Fbar importantly indicated, (and as I had forgotten), the differences in firmware would be solved by the transplanting of the EEPROM. The rest of information being stored on a special area of the sectors (I recall it isnt necessarily the first few sectors).

I hope you arent being charged an arm and kidney for it

Myself and fzkabar I'm sure will be glad to help you when you get it - at attemtping to transplant it.

-Keep in touch.