Hello,

can someone point me to a guide with the best practice to test a pcb for Electrical Failure of the board components ?

In particular I'm looking for information on Samsung drives.


Thank You

(1) Inspect the board for visual damage.

(2) Does the drive spin up? If yes, PCB is probably OK. If not, PCB is probably bad.

(3) Check the TVS diodes and protection devices (fuse, polyswitch, zero-ohm resistor).

(4) Check onboard regulators for correct output voltages. Test for shorts on the outputs. If there is a short on the negative preamp supply, disconnect PCB from HDA and retest. If short goes away, then preamp is dead.

(5) Connect to the board's serial console. Is there any output? If yes, then MCU is working, at least partially. Are there any diagnostic messages? Error messages?

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A backup a day keeps DR away.

Where I can find a scheme for the correct location of those elements ?

You could do your research backwards, meaning search the web for ANY HDD schematics, then look on HDD donor sites or ebay for that hard disk.

other way round likely to turn your hair as grey as my beard.

Since schematics are not available, I generally use a Huntron to compare the signatures of a good with a suspect PCB.

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http://www.datasaversllc.com

I go all warm and fuzzy when folks mention engineering solutions and test gear
<ahem> anyways .....

OP:
You could also try looking up other contributions and tutorials from fzabkar
Pure quality.

Kern

edit: HaQue, greybeard ..... oooh there's a nickname a brewin =)

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Голод не тётка!

Tutorial - Linear and Switchmode Regulators used in HDDs:
http://malthus.zapto.org/viewtopic.php?f=59&t=231

Tutorial - how to locate the basic test points of an unfamiliar HDD PCB:
http://www.users.on.net/~fzabkar/HDD/Tu ... 0411N.html

_________________
A backup a day keeps DR away.