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What's gone well for you recently? No matter how big or small.

cstanton

I took a couple of weeks off work, as much as you can when it's in the middle of a lockdown pandemic in the united kingdom, and I had a couple of wins myself.

blown up chip

For many years I kept hold of a computer hard drive that had died on me, of all things the microcontroller on the control board blew itself up. I had looked for a replacement control board online and at the time they cost £100+ because this was such a common problem, however recently I looked again and found that it was on ebay for £6, with a 50/50 chance of being the wrong model.

 

image

 

I took a gamble. A direct swap of the board isn't what works with this, as you can even see highlighted in the ebay listing screenshot, each drive has a BIOS chip on it flashed with the necessary settings for the platters, sectors, etc. of the hard drive. Without the right BIOS chip, you'll just get garbled data or clicking.

 

Time for a bit of desoldering and kapton tape.

 

image

 

As luck would have it, it worked! My hard drive was brought back to life, and I was able to recover my data once more.

 

image

 

I'd say that is a good 'win' for £6 and a reflow station image

 

What's gone well for you recently?

Parents

  • A brave repair. Well done. Usually chip damage like that is due to sudden and severe overheating from something like the current associated with a short to mains voltage. Which may be not be the chip's fault at all.

  • in reply to dougw

    Eh not necessarily. A spindle motor that's a bit jammed due to wearing bearings will draw high start-up currents which can cause those chips to fail given enough start-stop cycles. Likewise, a noisy DC power supply with lots of ripple may give them enough stress.

     

    The chip itself (ST SMOOTH) is actually a combination motor driver chip if I recall correctly - does the spindle motor and head positioning voice coil motor. It's one of the few chips on the PCB that actually deals with the ATX 12V rail and the bulk of the power running through the drive.

     

    The EEPROM chip contains the drive parameters, sometimes even a snippet of firmware, but the bravest of souls could try desoldering it with the "solder blob" and wick method if they don't have a hot air gun - it usually works just fine presuming you're quick.

     

    - Gough

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  • in reply to dougw

    Eh not necessarily. A spindle motor that's a bit jammed due to wearing bearings will draw high start-up currents which can cause those chips to fail given enough start-stop cycles. Likewise, a noisy DC power supply with lots of ripple may give them enough stress.

     

    The chip itself (ST SMOOTH) is actually a combination motor driver chip if I recall correctly - does the spindle motor and head positioning voice coil motor. It's one of the few chips on the PCB that actually deals with the ATX 12V rail and the bulk of the power running through the drive.

     

    The EEPROM chip contains the drive parameters, sometimes even a snippet of firmware, but the bravest of souls could try desoldering it with the "solder blob" and wick method if they don't have a hot air gun - it usually works just fine presuming you're quick.

     

    - Gough

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