Electronics Forum | Thu Mar 30 08:38:58 EST 2006 | Dan
We have this panel that is Gold Flash. Am I correct in assuming this is technically a lead-free panel then? We are running a WS paste, and the QFN28 has balls of solder instead of a fillet. My Max temp is 216, and the TAL was between 52-57 secs with
Electronics Forum | Thu Mar 30 08:59:46 EST 2006 | Dan
Yes the balls are at the outer edge. The chips we have are not showing exposed copper, but the lead-free finish...
Electronics Forum | Thu Mar 30 08:48:37 EST 2006 | russ
So you have solder balls at the outer edge of the part right where the pad goes underneath? If so you just have too much solder but I wouldn't worry about them. the solder usually does not wet to the edges of these parts because of the exposed copp
Electronics Forum | Thu Mar 30 09:32:54 EST 2006 | russ
Not arguing dan, but are you positive that they are not copper? anyway, what is happening is as the parts sucks down onto the board from reflow the extra paste is notnecessarily sqeezed out but it has no place to go. So it will form this ball on th
Electronics Forum | Thu Mar 30 10:21:44 EST 2006 | Dan
Sorry about that(My bad), they are copper. I believe the same thing, we need to reduce the appatures as we are already at 5mil. Our main problem is the customer...Their tests were failing and for some reason they touched that part up, and then the un
Electronics Forum | Thu Aug 24 06:58:19 EDT 2006 | davef
Darby National published stencil recommendations for their LGA in the "SMT Assembly Recommendations" section of: http://www.national.com/an/AN/AN-1187.pdf Is it possible that Silicon Laboratories published a similar document for your Cygnal CP2101?
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