OA75794 HDD Motor Controller Chip - info needed

[dicky96]

Hi guys

Does anyone know where I can find a datasheet for this HDD Controller chip from a Hitachi 1TB sata drive?

Also where I can buy these chips (UK) or if there is a compatible part number? I think the part number is 0A75794 (see pic)

I'm pretty sure the motor controller chip has failed on this drive as it gets hot and the drive does not spin up though I can hear the heads moving. Also there is a short circuit to ground from either side of the inductor marked 100 which is near the motor controller.

Cheers
Rich

[ala_borbe]

Re: OA75794 HDD Motor Controller Chip - info needed

buy donor hdd on ebay or similar

also if motor had stuck similar syptoms so it could be the motor itself

[dicky96]

Re: OA75794 HDD Motor Controller Chip - info needed

OK Thanks, I have seen donor boards (or even supposed working ones) I just wondered if replacing the driver IC is cheaper as it is not so difficult to solder chips of that pin pitch - i've done similar 48 pin packages on LED TV repairs no problem.

Is it possible to build some sort of test rig using an arduino or similar to spin a HDD motor so you could hear it moving? As there are only 4 connections to the motor that would seem not so difficult to do, it must be a matter of pulsing the pins at the correct phase.

That would be a rather useful piece of test equipment to prove if a motor is physically stuck or not

Cheers
Rich

[ala_borbe]

Re: OA75794 HDD Motor Controller Chip - info needed

I havent seen that anywhere but you can heat motor with hot air gun and then connect to pc and try while its hot, it should spin for a while

[FIGURETECH]

Re: OA75794 HDD Motor Controller Chip - info needed

EDUCATIVE replies

[FIGURETECH]

Re: OA75794 HDD Motor Controller Chip - info needed

WHAT are the actual voltages on a HDD thanks in advance. I am new in the field I wish to know the basics first. The name of the voltages and where can I read them easily on the board