On Sun, Jul 02, 2006 at 02:55:33PM -0400, Dave Lag wrote:
> I wasn't sure...goggle google...seems like its a corrosion issue?
> 
> http://www.ethanwiner.com/St-Synth.html
> June 1979 issue of Recording-engineer/producer magazine
> 
> By the way, if you decide to use IC sockets, never use a gold plated 
> socket if the ICs have tin plated leads or vice versa. Many people don't 
> realize this, but over the years, corrosion can result from the 
> dissimilar metals if even the tiniest impurities (like sweat or other 
> moisture) gets on the mating surfaces.
> 
> http://www.dsp.dla.mil/sustainment/PEMs_best_practices.pdf
> 
> Sockets are unreliable due to several things. These areas include 
> micromotion
> causing fretting corrosion. This is corrosion formed by
> dissimilar metals at the board/socket/microcircuit interfaces and open
> circuits due to insufficient contact pressure or from vibration and
> shock. If the sockets have to stay on the board, request that there is a
> common metal finish on the sockets contacts and the microcircuit
> leads.

Very interesting document!

So given that almost all ICs, especially in DIP format, are tin and or
lead finish where are all the gold-plated sockets that I see absolutely
everywhere in catalogs and surplus pins used?

-- 
pete@petertodd.ca http://www.petertodd.ca
-- 
http://www.piclist.com PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist