Poll: Do you use chip sockets?
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Socket to Me?
09-28-2021, 04:32 AM
Post: #11
RE: Socket to Me?
(09-28-2021 12:29 AM)jjohnson873 Wrote:  Desoldering can delaminate the copper from the pc board if all the solder isn't removed and forcing the integrated circuit out of the pcb holes or the surface mount fingers.

If the holes are plated through, the pads are like the flanges of a rivet, so delamination should not be a problem. It is very difficult to remove an IC from thru-plated holes though. The times I've needed to do this were always on cheap ICs where it was well worth it to sacrifice the IC to spare the board, so I'd cut all the pins, right at the body, then pull them out one by one, then clean up the holes. When the IC cost us 14 cents and the bare 12-layer board with no parts on it cost as much as $60, the decision is easy. I've had to do that when we were still using thru-hole, and to get maximum density, resistors and diodes went under the ICs, and manual stuffing led to the occasional error.

Now of course we're using SMT, and sometimes parts on both sides, and boards much smaller and less complex; so if the occasional repair needs a new IC, the whole board gets replaced. So far I have not heard of any IC failures on these though, and there certainly aren't any parts under the ICs to replace.

The only time I put DIPs on both sides, it was a small board with one IC (an EPROM) on the back, with a socket. The socket would be soldered in first, then they cut the rails holding the two sides together so they wouldn't be in the way of soldering the rows of pins coming through from ICs on the front. Without the socket, you'd have to apply the solder to that second side to the top of the pins. That would work in this case but it was an EPROM anyway which might need to be removed for reprogramming at some point.

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Messages In This Thread
Socket to Me? - toml_12953 - 09-27-2021, 11:15 AM
RE: Socket to Me? - BillBee - 09-27-2021, 12:55 PM
RE: Socket to Me? - DA74254 - 09-27-2021, 04:19 PM
RE: Socket to Me? - Garth Wilson - 09-27-2021, 07:43 PM
RE: Socket to Me? - toml_12953 - 09-27-2021, 07:46 PM
RE: Socket to Me? - teenix - 09-27-2021, 11:21 PM
RE: Socket to Me? - jjohnson873 - 09-28-2021, 12:29 AM
RE: Socket to Me? - Garth Wilson - 09-28-2021 04:32 AM
RE: Socket to Me? - teenix - 09-28-2021, 04:54 AM
RE: Socket to Me? - Jim Horn - 09-27-2021, 07:55 PM
RE: Socket to Me? - Craig Bladow - 09-28-2021, 01:00 AM
RE: Socket to Me? - teenix - 09-28-2021, 01:29 AM

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