I have a module I’m putting together and it has two 16 pin ICs and one 8 pin ICs. The 8 pin IC is fine, but the 16 pin ones (one to a greater degree than the other) won’t stay in their sockets. The least force will dislodge them. I’ve had one literally leap out of the socket and land a couple inches away while I was pressing a scope probe to the other side of the board.
The sockets – all three – are solder type (not machined type) from Tayda:
As I said one IC is less secure than the other but even the better one comes out very very easily. I’ve tried using different ICs. I tried putting one into another (un-mounted) socket, same thing.
I bend the IC legs in by pressing against the work surface until they fit in the socket.
I’ve built stuff for years including a couple dozen modules in the past year and haven’t had this happen on any of them until now. Including some with 16 pin ICs in Tayda sockets.
Could it be a duff batch of sockets? Does that happen? Is there a better way of bending the legs? Should I from now on test putting ICs in sockets before soldering the sockets? Can this board be saved?
You can buy IC leg straightener tools. I haven’t had this problem myself to the extent that I needed a tool, but it’s worth a try as they’re not that expensive.
That sounds like a production error to me. Simply use other sockets. It’s very annoying, but it just happens sometimes. Some time ago I bought 100nF ceramic capacitors and none of them had more than 35nF … shit happens
So I wouldn’t leave the ICons in the socket when soldering. I think that a big advantage of sockets is that the IC doesn’t get that hot and of course that you can change it quickly.
What I still don’t understand, where is the problem with unsoldering the socket to insert a new one? Don’t you have a desoldering pump?
I can empathize with people who don’t like to desolder. It feels like you’re doing a lot of work to move backwards. Like when you’re threading a maze and hit a dead end, retracing your steps is frustrating.
I find the pumps often work best for clearing out holes after the component was removed. I like the mg chemicals resoldering braid, it’s expensive but IMHO worth it over other braids. It’s like magic how well it wicks solder up and out of a board.
The hot air definitely helps on sockets and heder’s…but I still usually wind up purposefully breaking the socket and resoldering the pins one by one.
Though sometimes I can get them off by adding more solder. The idea is more solder has more thermal mass so will stay liquid longer making it easier to get all of the pins loose at once.
I have seen this in server racks where the board is screwed too tight to the mounts, forced in badly or at an angle that twists the PCB.
Over time the board straightens out and can squeeze mounts and sockets popping things out.
I say seen… that’s 3 times in 40 years.
Having enjoyed your YouTube videos I look forward to a full expose of this phenomena.
Will you test square and round socket types? Sorry, I forget the proper names for them.
Try not straightening the pins so much, the friction from a sharper angle might secure them more. Try reflowing the ic sockets (without the chip inside of course). It’s possible the pins for the socket shifted when you soldered in place, which gives less tension.
First thing I checked when reading this was today’s date. No, not April 1st. This sounds hilarious, if you don’t mind me saying so. But never came across this myself.
