Removing DIL IC's

[19Seventy7]

Hi,

I need to replace an IC which has 8 legs. I only have a soldering iron that I can use to de-solder the legs. I have tried but no luck.

The area it's in is quite crowded so have limited space to work.

Does anyone have any tips or tricks on how to remove it?

Thanks

[SiriusHardware]

Caution #1: Can you see any little red blobs squeezed out from under other components (resistors, capacitors) in the surrounding area? If so the chip is likely to be glued down. That will require more careful handling.

But if not, just flood both 4-pin sides of the device with lead-tin solder to make it a 'two-pin' device, and use two irons to melt the solder on both sides at the same time: Lift the device off the PCB with the same two irons, using them as tweezers, when the solder on both sides is melted.

Edit: Just read your edit! In that case snip all the pins off close to the IC body and desolder them as individual 1-pin devices. Melt the solder on each pin in turn on the track side and pull the pin out through the melted solder, using tweezers, from the component side.

[G6Tanuki]

I find the quickest way - same applies to classic 0.1-inch-pitch DIL chips - is to cut the legs off the chip-body and then remove each remaining leg one at a time.

[19Seventy7]

Hi,

I did think about snipping but I don't have anything thin enough to get in and snip them as they're very close together.

Thanks

[Goldie99]

If it's a single sided board, de-soldering braid & flux works well also, and is certainly useful to 'clean up' before installing the new IC

[SiriusHardware]

You can use a scalpel to slice the pins off close to the body but in that case be careful not to cut too deep, otherwise you may slice through PCB tracks as well.

[MrBungle]

Edit: just seen edit.

Cut legs off close to the IC body and desolder each one individually. You will probably need to add solder first then pull out when wet then clean the holes out.

[TonyDuell]

I agree, if you don't care about the old IC, cut the pins off and remove the body separately. If you think you might be doing this often, buy some decent small cutters

The best way I've found to clean the hole out after removing the cut-off pins is to elt the solder with an iron on one side of the board and use the solder sucker on the other side of the board (obviously on the same hole).

[19Seventy7]

I cant find anything indoors that is small enough and sharp enough to cut through the legs. I'll have a look round shops tomorrow to see if I can find anything suitable, or if not ill get some de soldering braid.

Thank you for your help

[Radio Wrangler]

X-acto knife or a scalpel. Pretty essential in any electronics toolbox. Life will become so much easier.

David

[Goldieoldie]

Best method is to use chip quik
It's a low temp solder that stays melted for a longer time than standard solder
Just melt some on the pins on all sides of the chip
Then just lift the chip off .Its that simple !

[McMurdo]

a trick I sometimes employ is to use the cutting disc on my dremel to shear off the IC pins. This is sometimes necessary where the board is poor quality and the force of the snips on the legs is enough to damage the tracks of double sided boards. But dont grind too deep!!

[Station X]

Originally Posted by 19Seventy7

I cant find anything indoors that is small enough and sharp enough to cut through the legs. I'll have a look round shops tomorrow to see if I can find anything suitable, or if not ill get some de soldering braid.

Thank you for your help

I find a Stanley Knife with a NEW blade works fine. You need to be careful not to cut the tracks too though.

[Craig Sawyers]

Buy a pair of decent cutters. They make short work of cutting the legs off flush to the body of the IC (or resistor etc).

Because I do a lot of construction I use Lindstrom cutters, which are stupidly expensive (there are even more stupidly expensive ones than Lindstrom though!).

But there are half way decent ones from Farnell for less than a tenner that will cut copper wire up to 1.3mm, and would be a fine investment.

Craig

[WaveyDipole]

If budget is an issue, these are extremely cheap, but they are sharp and work pretty well for small wires and component legs.

https://www.ebay.co.uk/itm/Durable-E...e/143188855072

[poppydog]

Careful with the soldering braid on thin traces. I pulled off 2 or 3 of the very thin solder traces on a Samsung t-con board a while back whilst replacing a chip, its very easily done. The chip cost pence but the replacement board cost me a tenner

Regards Poppydog

[julie_m]

If you have a circuit diagram (or can see where the other end of the track ends up) you can always use a bit of "bodge wire" (super thin, single-strand insulated wire as used in wire wrapping tools) soldered to the component pins to bypass the damaged portion. Be sure to remove any loose bits of copper to avoid short-circuiting to anything else.

It won't win any awards for beauty; but if it's the difference between that and a new one, it's worth a go!

[Maarten]

Desoldering SMD on densely stuffed boards such as a TCON, is best done using a hot air station.

[ricard]

I would have thought that a decent pair of relatively pointy wire cutters would be high on the essential tool list for any workshop. It's certainly one of the first tools I'd bring if I needed to go somewhere to do some work (the others being a pair of (pointed) pliers and a small assortment of screwdrivers).

[Station X]

I have some relatively pointed wire cutters. They're great for valve work, but it's very difficult to cut DIL IC leads with them. You just can't get in close enough.

I remember buying a very small pair of wire cutters many years ago which were ideal for the job, but unfortunately they disappeared and I've used a Stanley knife ever since.