Author Topic: Need some PLCC socket/chip testing tips  (Read 838 times)

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Offline skysurf76Topic starter

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Need some PLCC socket/chip testing tips
« on: January 31, 2021, 01:44:59 am »
I need to monitor some signals on a chip in a 44 pin PLCC socket and I was wondering if there is enough room between the socket connectors and the chip pins to insert a small wire as a test lead?  I was wondering if anyone had any experience with this, and if so any other tips and trips would be GREATLY  appreciated.

Thanks!
 

Offline Alex Eisenhut

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Re: Need some PLCC socket/chip testing tips
« Reply #1 on: January 31, 2021, 02:41:02 am »
That's old stuff. On the sockets I've seen  there is an opening next to each socket pin where you can jam a small piece of solid wire to access the signal. Don't touch the pins of the PLCC itself, they have a habit of squishing inwards and then not making contact properly with the socket.

In other words jam a piece of wire between the body of the socket and the contact of the socket in the "pocket". It's convenient.

I don't think you can break out all the signals that way though, it's not terrible solid IME.
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Offline PlainName

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Re: Need some PLCC socket/chip testing tips
« Reply #2 on: February 01, 2021, 04:21:17 pm »
The simplest way to do it, money no object, is with something like the Winslow W9176 (crappy photo attached).

If you like that kind of thing there is a catalogue full of them: Winslow catalog (25MB pdf)

There are (much) cheaper clip-on breakouts if your chip is soldered on the board - you can probably replace the socket with a soldered chip if you don't need to remove it again. Although a quick blast from a hot air tool would get it off easy enough.
 

Offline skysurf76Topic starter

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Re: Need some PLCC socket/chip testing tips
« Reply #3 on: February 02, 2021, 01:37:56 am »
Thanks so much Alex. Your post actually lead to the solution. While probing between the socket frame and socket pin with needle probes the test on the device passed that was failing previously.  The pressure against the socket pins forced them to make good contact with the chip's pins. We are going to replace the socket.

Dunkem, I was doing some searching and came across that, and it would have been the perfect solution, but unfortunately purchasing it would require several months in my situation.  Good find though. It would have been my ideal solution.
 


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