Hi all!

Got a fresh new beast to deal with that I've never seen before...a PGA-to-SMT socket. When you look at the board, it looks like a BGA would go there, but actually
it's a PGA socket that is soldered to SMT pads...this is a fairly dense socket, 50-mil spacing. The history is that the yeilds are terrible, and 99.9% of the time when the assembly doesn't play, it's a solder issue with the sockets.

I've looked closely at these sockets, and they're not very precise. The pins are strange too. Each pin is about .145" long, .038" diameter, and have a little .018" diameter, .005" long nub machined into the end of each pin...this is what sits on the SMT pad and is soldered to. All the pins are inserted into a 1-inch square, .062" thick FR4 substrate to form the socket. Go to:

http://www.stevezeva.homestead.com

To get a look at what I'm about to deal with...I've noticed some coplanarity issues with the pins too. I've got some ideas to try and deal with that. But have any of you ever dealt with these little "jewels"? Got any tips?

By the way, these sockets MUST be used, no choice...

-Steve Gregory-