Samsung HD250HJ PCB Compatibility

[mikail13]

Selam Everbody..!
i have Samsung HD250HJ that' not spin.
5v TVS diode was burnt.
removing or changing doesn't help me.


i bought a same disk that has same pcb number.
but it's useless too. disk spins but can't visible .

unfortunately there is no rom chip on the Pcb.

is it Pcb or disk problem?

why the pcb swap is useless at old model Samsung disk?
is the rom data in main chip ?

[MindMergepk]

try to adopt pcb instead of straight swapping.
hotswap+adopt

[mikail13]

try to adopt pcb instead of straight swapping.
hotswap+adopt

how could i do that?

[MindMergepk]

start donor drive:

> check and read all modules
> send standby command
> switch pcb to patient drive
> recalibrate
> verify heads are fine !
> write two overlay modules from donor drive backup

good luck

[northwind]

This method works, but it can be quite dangerous if the OVLYs are not compatible, you can end up with a bricked drive.

I would start by placing a donor pcb and checking the terminal output...

[mikail13]

i have a wdr 6.0
it reads samsung hdd.

can i write with it.

like this video.

https://www.youtube.com/watch?v=Z3Z7U91SzSc

[mikail13]

in that case i need SRT for Samsung

i found a link but this is Russian site but i am not fool to download.

and now i realise that B240 diode is short only when pcb screwed

only B240 is normal.

is this a preamp failure?

[fzabkar]

and now i realise that B240 diode is short only when pcb screwed

only B240 is normal.

dont know what u mean

is this a preamp failure?

probably

[mikail13]

B240 is normal when i remove the board from disk.

also B240 normal when i desolder from pcb. (i know no need that but at first i thought diode gone)

and also
when i screw donor board to the patient disk it spins.
pc can' t recognise disk but B240 seems normal. not short.

i don't understand too.

[fzabkar]

There are two B240 diodes in this photo:
http://thumbs.picclick.com/00/s/MTIwMFgxNjAw/z/6XgAAOSwxg5X0mbh/$/250-GB-Samsung-HD250HJ-PN-340421IPA64082-TRIDENT3-_57.jpg

The vertical one appears top be associated with the negative supply for the preamp. The horizontal one looks like it might be part of a boost converter.

If you can supply a photo of your own, I might be able to identify the voltage test points.

[mikail13]

in that case this is boost converter.
horizontal one.

Native pcb looks like battlefield. but functional. i tested components that i solder.

Only Main (marvell) chip heating up a little. Other's always cold


and thank you for help.

i'm sorry that i had to upload the original pic at first message.

I've never worked so hard for a pcb before. this is strange fault for me.
It only took 2 days to find the donor pcb.
I selected from about 1000 hdd.

Attachments

[data-medics]

That PCB looks pretty crusty, I'd say you should forget about repairing it. It's also not one that requires any adaptation as far as I remember. You just need to match the model and firmware version of the drive to find a compatible replacement.

[fzabkar]

Measure the resistance between the Gnd pin and each of the +5V and -5V pins at the HDA connector. This will tell us if either of the supply rails is shorted to ground. Do this in the absence of power, and with the PCB on and off the drive.

BTW, I'm not sure whether the diode is part of a boost converter or some other topology. Your photo is too poor for me to work with.

Attachments

Preamp_supplies.jpg (54.76 KiB) Viewed 13138 times

[mikail13]

Looks like pcb have a +5V and -5v problem it's related about head connector or Preamp.

5V TVS diode had already burned.

broken pcb never work with health disk.

after the measurement i plug the power to health pcb+patient disk.

last week it spun.

but this time weird sounds came out. chattty ! chatty !
i think that head was squeezed.
and now no spin.

thankfully donor board is O.K. at least.

Attachments

[fzabkar]

It appears that your patient's preamp has a short between ground and the -5V supply, ie it is dead.

I don't understand why the last set of readings shows a short to ground at +5V ... unless the problem has spread.

[mikail13]

I don't understand why the last set of readings shows a short to ground at +5V ... unless the problem has spread.

i'm sorry that the last +5v is 1,5 k Ohm

and thank you very much for your help..