Is it only the U12 chip that I need to transfer?


hard drive model is WD3200BPVT-24ZEST0 with a back sticker 2061-771672-R04 04RD7 on the PCB board.

When swapping PCB boards, is it only the U12 chip that needs transferring or the Marvell MCU also?
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More about chip transfer
  1. Just transfer U12.

    You should only consider transferring the Marvell MCU if location U12 is vacant, in which case the flash memory will be embedded within the MCU. However, even in such cases there are ways to extract a ROM backup from the System Area on the platters (using specialised data recovery tools).
  2. What happened is the following stupidity:

    I connected a 12V power supply to my 2.5" hard drive by mistake for about 1 minute, then when the drive heated up a bit I realized what I have done. Next I connected it correctly and the hard drive did not spin or get recognized by my computer anymore.

    Next I started googling and reading all sorts of websites, like anyone else would do. So I started looking for a replacement board 2061-771672-004 REV A
    I found it at hddzone(dot)com and ordered a replacement board which did arrive. I swapped it with my burned PCB board and the drive started spinning, but now clicking about 4-5 times and then spinning down to a turn off. The compuer did not recognize the hard drive either.

    Next I swapped the U12 Rom Chip from my dead PCB to the new board that arrived but the simptoms were the same spins up, clicks about 4-5 times and then spins down to a stop, not recognized by hard drive.

    even though both boards are engraved 2061-771672-004 REV A
    I was puzzled so I looked at the original board and the new board that was sent to me closly, so here are the differences I found:

    the back PCB sticker reads...
    original PCB: 2061-771672-R04 04RD7
    replacement PCB: 2061-771672-F04 AD

    also I noticed that the main 3 large microchips on the board are all different. 2 are same brand but different part numbers, and 1 is totally different brand.

    Could cause of no recognition and clicking be associated with the non matching matching part numbers on the main (large 3 ) chips of the PCB board??? What are the chances of U12 BIOS chip burning up, or pre-amp on the reading heads when you connect a 12V power instead of 5V?
  3. The fact that your drive spins with your replacment board confirms that your U12 transplant went well. However, it could be that the overvoltage killed the preamp on the headstack inside the HDA.

    On 3.5" drives the preamp usually gets two supplies -- the +5V supply from the SATA power input, plus a -5V supply derived from an onboard switchmode regulator.

    I suspect that your preamp might be running from a single supply, either the onboard +3.3V supply, or the external +5V supply. I would use your multimeter to test for continuity between the +3.3V test point and each of the preamp pins, particular those with the heavier copper traces. The 18-pin preamp contacts are located at the long end of the board. Also test for continuity between the preamp pins and the +5V SATA power pins. This should tell you where the preamp gets its power from.

    As for the chip numbers, what are they?
  4. maybe this will explain

    so in other words the 12 volts went where the orange section is supposed to go in the link you sent me.
  5. 12V was applied to the drive's 5V pins. This means that the motor controller IC is most probably dead. You now need to determine whether there is any connection between the SATA +5V pins and the preamp contacts. If so, then the preamp will most likely be dead.
  6. i really don't know exactly how to test the preamp... are there any photos or video or something I can follow??? I want to determine if it is the preamp. I will post tonight the part numbers on both boards... I still keep thinking it maybe the board diffrence, I don't know. Do you think that maybe because the 3 chips are different compared to the original board, then that's where the issue maybe?
  7. The differences in the part numbers may or may not matter. I don't know enough to be certain. However, I do know that the SDRAM part numbers can differ as long as the capacity is the same.

    As for testing the preamp, all I'm asking you to do is to use a multimeter to measure the resistance between the +5V pins in the SATA power connector and the 18 pins at the preamp connector. If you measure zero ohms at any pin, then this will tell us that +5V is powering the preamp inside the drive. This will be bad news for you.
  8. i see... thank you for clarifying... I will do that when I get home.

    I will measure the resistance as you said and I will post the part number comparison of the boards

    thank you
  9. before I do the testing... should I have the PCB screwed on the hard drive while I test the resistance or not? Should I do the resistance test with both PCBs?
  10. I would test the new PCB on its own. At the moment we are just trying to find out how the board is supposed to work.

    BTW, the following article identifies the various HDD components:

    Here is the preamp on the head stack:

    ... and the HSA connector:
  11. So here are some details:

    my original PCB board has 3 large chips, i will call them U1, U2 and U5:

    U1 reads:

    U2 reads:
    SAMSUNG 122
    H2816 YEE019GNC

    U5 reads:
    117 BOY

    Now for the replacement PCB board again U1, U2, U5 chips:

    U1 reads:

    U2 reads:

    U3 reads:
    119 BOY

    by searching I think ( i maybe wrong ) the cache maybe different... you tell me

    I did the resistance test from the power connector the the 18 connectors at the HSA and this is what I found out:

    with the original PCB the resistance goes to zero (closed circuit) at connectors 1, 8 and 10, but with power supply ON (correct power supply 5V) plugged in, the voltage does NOT exceed 3 volts at connectors 1 and 10 or any other point, except for connector 8 the voltage goes to 5 volts.

    with the replacement PCB the resistance goes to zero at connector 8 only, with the power supply ON the only place the voltage goes over 3 volts is at connector 8 which reads 5 volts.

    what's my next step??? I really don't want to go into the heads.... looks scarry, but I am willing to do what you say... i need to recover the data somehow.
  12. SH6601AF (U1) is the controller for the spindle motor and voice coil. It probably also controls the switchmode power supplies (+1.2V Vcore and +3.3V Vio).

    88i9045-TFJ2 (U5/U3 ?) is the Marvell MCU.

    K4H281638O-LCCC and W9464G6JH-5 (U2) are 16MB (8M x 16) and 8MB (1M + 4 BANKS + 16 BITS) DDR SDRAMs, respectively. Therefore they are different, but I don't know what effect this has.

    I have uploaded my HDD IC database here:

    ISTM that the MCUs and motor controllers are identical. The other numbers are RoHS materials codes (eg G4), date codes (122, 117, 1120, 119), batch codes, and country of manufacture (CN = China ?). The date codes are expressed in YWW or YYWW (Year / Week) format. For example, "122" denotes week 22 of 2011.

    Your resistance measurements would suggest that the preamp does indeed get its supply from the +5V input, in which case it would probably have been destroyed by the overvoltage. Therefore ISTM that your DIY efforts have come to an end. AISI your only option now seems to be professional data recovery. Sorry. :-(

    BTW, your resistance measurements in respect of pins 1 and 10 are puzzling. I can't understand what is going on there.
  13. So how do I go about chooseing a donor drive to extract the preamp (heads) ? What do I need to look for in a donor drive so that the heads and the preamp match??

    is there a tool I can purchase to do the job?

    or is there a more accurate measurement I can on the preamp? Perhaps directly on the HSA connector??

    Explanation of DCM:

    HddSurgery - Tools for data recovery professionals: (Head replacement tools)

    Head Swap videos: (HDDS WDC 2.5"-3.5" Ramp Set)

    As for measuring the preamp at the HSA connector, can you upload detailed photos of both sides of the PCB near the preamp contacts?
  15. i just want to say thank you helped me with lots of info!

    I see that it is a very complicated and fragile job from here, that is if I will have to exchange the preamp... this is best to leave to professionals. Without the correct conditions and tools, I could mess things up permanently.

    I will give it a try with another board which has the correct DDR SDRAMs and if that doesn't work then it is highly suspected that the preamp is gone.

    thanks again!
    I will report and tell you what happened next... will come back soon and update.
  16. just an update on the resistance test...

    I redid the resistance test from the power connector the the 18 connectors at the HSA on the board with a digital multimeter this time, I found out:

    with the original PCB the resistance goes to 0 ohms at connector 8 ONLY, but with power supply ON the voltage goes to 4.8 volts at conector 8. Same thing with the new PCB

    last time I was using an older multimeter with an arrow pointer, but this time a digital (more accurate), what looked like 0 ohms at connectors 1 and 10 was simply a very low resisitance.
  17. I still can't imagine what those pins are for. You could possibly determine their function by examining the signal and power traces.

    If you want to map out the pins, I would use the good board. First determine which pins are grounded. Pin #1 looks like it connects to ground. If so, then this would suggest that there is a low resistance between +5V and ground, probably due to a faulty component. However, if pin #1 is indeed grounded, then it should measure 0V when the PCB is powered up.

    Next look for two heavy traces running in parallel from the preamp/VCM contacts to the motor controller IC. These will be the voice coil terminals (possibly pins 10 & 12).

    Next there will be two pairs of thin signal traces running toward the MCU. These will be the Read/Write signal pairs for the Read Channel. They will be terminated with small resistors.

    In the following photo clip, the Read/Write pairs appear to be 5 & 7 and 13 & 15:

    Pins 4 and 6 have heavy traces. They could be power or ground pins. I would test for continuity with the +3.3V test point on the PCB, or with the two coils near the motor controller.
  18. if the hard drive has a single platter, as it does in my case, how easy will it be to get the data out? what donor drive should I use to switch the platter with? even if I find a donor drive to switch the platter with do I still need to implant the U12 bios chip?
  19. u12 is matched to the platter
  20. what happens if the U12 is dammaged?
  21. it fails its checksum test and the drive doesnt spin
  22. so I took it to a data recovery company. they made it spin and recovered most of the data. $800 later :|

    oh well... next time I need to be careful how I connect things!
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