68kMLA Classic Interface

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Replacement carrier for 344S0603-B
Posted by: plexxer on 2025-06-05 14:07:48
I have an SE FDHD with serious corrosion on the carrier for the 344S0603 VLSI ASIC IC. Is this part a drop-in replacement? https://www.mouser.com/ProductDetai...GVfnNGsEuBIvTaGUVo0saillzr1_jmHvqYVi-yP255akS

IMG_1415.jpeg
Posted by: shirsch on 2025-06-09 07:08:23
The Mouser part is an 84-pin PLCC socket and thus should be the correct replacement part. It's incredibly easy to yank out via barrels when attempting to desolder the old part as a unit. If I were you I'd consider crushing the old socket with pliers to the point where you can pull the pins individually from the top.
Posted by: plexxer on 2025-06-09 08:01:20
The Mouser part is an 84-pin PLCC socket and thus should be the correct replacement part. It's incredibly easy to yank out via barrels when attempting to desolder the old part as a unit. If I were you I'd consider crushing the old socket with pliers to the point where you can pull the pins individually from the top.
Thank you, that is incredibly helpful. Unfortunately, this board needs several ICs desoldered, including the 40 pin DIP serial controller and the power/video molex connector. Do you have any additional tips or advice?
Posted by: bibilit on 2025-06-09 10:05:40
This board seems to have a battery bomb issue in the first place, not impossible to fix but be prepared to a lot of work.
Posted by: plexxer on 2025-06-09 12:15:16
This board seems to have a battery bomb issue in the first place, not impossible to fix but be prepared to a lot of work.
Yes, the damage is significant. The board pictured was manually scrubbed with distilled vinegar and then run in an ultrasonic cleaner with Raytech CR for 5 minutes @ 60C. I am at the point where I am going to start removing components and doing spot-cleaning. There are at least 9 packaged components I am going to have to remove, along with various resistors, diodes and caps. Luckily, the Apple-specific ICs (other than one of the filters) seem to have all been spared.
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