Can i desolder and resolder a buffer chip?

[tucocaps]

Sadly, I'm thinking the answer is "no" with my limited solder skills and equipment.

I have a 40 watt iron, a basic weller pot adjust station, and a number of butane torches. Also have some desolder braid, click type solder sucker etc.

I practiced the torch method on some memory chips, but those seemed to go a LOT easier than when I finally tried to remove one of the buffers on this panasonic sd board. A big problem seems to be the darn silicone they encase the outside of the chip legs with. How can I get it off? caulk remover won't touch it, and it does not melt. It burns badly, and appears to block heat from the torch to the pins.

I've got two of these SD, and I'd like to swap at least one chip from one to the other, but haven't even been able to remove one yet. Thanks for any ideas, and also any idea on how much heat those chips can take before they are destroyed.

[capkid]

Re: Can i desolder and resolder a buffer chip?

I use my finger nail to scrape off as much of the silicone as possible before I attempt a chip removal. Also, I would be very leery of using chemicals like caulk remover on a PCB.

Swapping chips, especially if there was silicone covering the legs, will be nearly impossible. A hot air station is the best tool for removing the chips, but a heat gun on a low setting can work in a pinch. You need to be sure to protect any nearby components or connectors from the heat, though. I normally use kapton tape, but several layers of aluminum foil might work, also. Installing a replacement chip will be the tougher part.

Here are some tips: https://www.badcaps.net/forum/showth...light=hp-t5054

[chappc]

Re: Can i desolder and resolder a buffer chip?

It is possible but difficult. Removing the old ic is the hardest part as it takes a lot of heat to melt the solder ground. I
I use acetone to remove as much silicone as I can then use solder wick and lots of flux on the legs. Then out comes the hot air gun, start on the other side melt the solder and then bact to the legs just don't damage the solder beds