Extracting and Reinstalling SMT IC

What type SMT parts? For many, it's possible. But if you're talking about a 144 pin quad flat pack, may be a different story. :)

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Hi Sam,

Could you explain how to extract the SMT ICs. Thanks

What type of package? There are all kinds of SMT devices.

But for any, with a hot air rework station, it's much easier than with a soldering iron.

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SeventhPrince??? wrote: : Hi Sam,

: Could you explain how to extract the SMT ICs. Thanks

As others have mentioned, what kind of package?

If it only has leads on two sides the way to rework them is with a special solder tip that is a "bar" shape. It heats all of the leads at once. A square tip that matches the outline of the IC leads is used for ICs with leads on all 4 sides. If it's a BGA (ball grid array... no visible leads on periphery) only a hot air rework tool will do the job.

Also, you could try carefully cutting each lead with sharp, clean cutters and removing the leads individually, then cleaning up the land pattern with solder wick and resoldering the part.

It's not an easy job to do with conventional soldering tools. You need a sharp pointed soldering iron and a magnifying light to do the job.

b.

Howard Electronics has some nice videos on removing SMD stuff. Dig around there are also many tech tips on removing them also

Could SMT IC be extracted and reinstalled with new ones? Could it be done with hand methods and without using SMT machines?

Thanks. SeventhPrince???

Thanks Sam.

I have successfully removed and replaced many surface mount chips (including large quad packages) using chipquik and techniques similar to those described on the page above. However, it's difficult to keep the chipquik melted all the way around the package with just a regular soldering station and a hair dryer. I use thin strips of stainless steel (sold as "matrix bands" by dental suppliers), sliding them between pins and pads one row at a time and leaving them in place while I work on the next row - solder doesn't stick to stainless steel, so when you get to the last row the chip comes off easily.

Sunny

Most certainly it can. Doing so properly requires the correct tools (fairly expensive), and a good deal of skill.

Under a few rare conditions, such as low pin count PLCC packages, yes. I've done it. However, I've never been entirely happy with the results. SMT desolder/resolder equipment is still the best possible way to do SMT repair and rework.

If you're looking for equipment to do so that won't require a second mortgage to finance, look here:

Happy hunting.

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For any chip that has visible pins such as a "SOTA" type, I've had good luck by covering the legs with solder. First you do one side, then the other, and sort of rock it up. Cover one side of pins with solder and move the iron up and down the length of the chip until the solder is good and molten. Using a jewelers screwdriver or a dental pick, ease that side of the chip up very slightly. Say, no more than about a 32nd of an inch. Do the same on the other side and keep repeating the process until the chip comes free. You can then use solder wick to clean up the globbed up solder on the PCB. The hardest part is, of course, installing the new chip, but with loupe goggles or a Luxor lamp, and some patience, you can do it. Oh, BTW, Hi all. I'm new to this group.