Hi, sorry to hear you cannot access your files, hard drive repairs are not supported but you can contact any of the data recovery partners on the WD support page, some of them can offer a free evaluation of your drive.
The SMOOTH chip controls the spindle motor and voice coil positioner, plus it also controls various onboard power supplies. The damage to your chip is on the side that controls the Vcore supply for the MCU plus the negative supply for the preamp.
I suspect that your drive sustained an overvoltage on the 5V input. To confirm whether this is the case, measure the resistances of the following components:
If your board has an 8-pin chip at location U12, then the most expedient solution would be to purchase a replacement PCB and transfer U12, or its contents, from patient to donor. The following PCB suppliers include such a service in the price:
That said, there is a high probably that the preamp on the headstack inside the drive has been damaged, in which case you will need to engage professional services.
First of all fzabkar it’s very nice to see you here !
Regarding the problem with this drive, i have one question :
With the new PCB does the drive spins and clicks or does it spins and sounds as trying to calibrate normaly without clicking and then it just doesn’t detect on BIOS ?
If the drive just clicks with the new PCB then most likely the pre-amp on the head stack or the heads themsefs are damaged and the drive must be opened on a hepa 100 clean room to have the head stack replaced for data recovery. This have to be done by a data recovery firm with the necessary tools and clean room.
If the drive sounds as normal then the problem is like already stated due to the fact that the drive have unique adaptives stored on the PCB ROM. Also the version of ROM on the donnor PCB might mismatch the version of perm ovl - Module 11 on the firmware stored on the platters.
If your drive have an external ROM chip you can just swap the ROM chip to the new donor PCB or if you are not good at soldering you might want to read the content of the chip with an external programmer like a willem and copy it over the new ROM chip like on this guide :
If your ROM is masked on the MCU (no rom chip on the PCB) you will need specialized tools to access the SA with “compatible” donnor PCB and get the necessary modules to re-create the original/compatible ROM (and ROM MODULES - Adaptives) and be able to make a pcb with a ROM code that will work for your drive.