Hi Peter!

If you go to: http://www.stevezeva.homestead.com you'll find a couple of pictures down at the bottom called Palladium and Palladium2 that show the solder joints on a 48-pin TI TSOP that are on a board here...actually there's about a dozen of them on the board.

I remember when we first started building these boards our inspectors were all up in arms about these parts "dewetting". The appearance of a palladium joint vs. a tin/lead stands out like a sore thumb especially if there's a tin/lead plated part right next to a palladium plated part.

The joints that you see in the pictures were formed using a Kester R560 water soluble paste. We also use Kester R244 NC paste here, and the joints will look about the same with that paste.

Got all the inspectors calmed down now by having them read that TI "Palladium Finish Users Manual" that I spoke of...

Back when this palladium finish first came out, it had everybody up in arms! TI just threw it out in the market without letting anybody know they were doing this, and I think that's what prompted them to write that users manual.

-Steve Gregory-

After much argument I am now getting microsections done to show that the
joints are good, however, do you or does anyone else know of any sites that
show typical appearance of joints formed to this particular lead finish?

When my microsection results are available I would be happy to share them
with anyone in a similar predicament.

Best regards,

Peter Barton