Hi,

I have a 2 TB HHD which has a faulty PCB. I have removed the PCB (100664987) and noticed that one of the LX7157B regulators is damaged (burned). I work as an Engineer at a factory where we produce PCB so I have the tools for replacing it. The problem is that I'm not able to find a place where they sell LX7157B. A new PCB for my HDD costs me 50 USD + 36 USD in shipping (I live in Norway) from Canada. I would like to try to find a LX7157B before I buy the PCB.

Have any of you looked into this before? I've contacted the LX7157B manufacturer and asked for some samples, but I don't think they'll send to private people. I've also searched and found a similar component called LX7157, but I'm not sure I should try this one. It's the same pinout, input voltage and output voltage.

Datasheet LX7157B:
http://www.microsemi.com/document-porta ... -datasheet

Datasheet LX7157:
http://www.microsemi.com/document-porta ... 8-lx7157ds

Best regards,

Even

ISTM that the components are identical except for their switching frequency (3MHz versus 2.2MHz).

I would go ahead with it, assuming there are no other problems.

That said, you might like to temporarily replace the chip with a high current LDO linear regulator, just to see whether the drive works. Follow the output of the chip to the SDRAM or serial flash memory, or maybe the MCU. The voltage ratings of the other chips should tell you the output voltage of the LX7157B. Alternatively, you could calculate Vout by examining the resistors in the potential divider at the FB pin.

_________________
A backup a day keeps DR away.

Hi,

Thanks for answering:)

I have now bought a new PCB, swapped the BIOS from my old PCB onto my new PCB, reset the heads that where stuck on the disk and booted up my computer.

My hard disk is now making a clicking noise like this: http://www.youtube.com/watch?v=qLdDjNcGPME and I'm not able to get past BIOS on my computer. After some clicks the disk just shuts down.

Have you heard of this before? Have I failed to reset the heads properly?

I did it like this: http://www.youtube.com/watch?v=7m5cil6KezI

Regards,

Even

Chances are the heads died during initial crash or ( most likely unfortunately ) when you removed them from the platters. If the flight height is affected you may have introduced additional damage to the platters. I recovered a raid 0 with 4 of those drives a few days ago. Had to use 3 donors to finish the image of the affected drive. They are a pain to get compatible heads. Also , one of the few 3.5 HDDs i saw with sticktion occurring.

Addendum : Opening the drive in the dirty environment is not the best of ideas. Introduces yet another possibility of fault , contamination of the platters. I glimpsed at the video , and there is truth to what the guy says , but its a coin toss. U may get lucky , u may not. Chances skewed towards not...

Hi,

Well that's a bummer. There's no important data on the disk so if it's broken it's no problem. To bad I had to buy a PCB, but thats the risk=/

Before I moved the heads, the disk was just spinning-stopping-spinning, making small buzzing noises, so I moved the heads. The buzzing was gone, but the clicking started.

If theres no way other than replace the heads, I'll just throw it in the trash.