Electronics Forum | Thu Jan 24 04:54:43 EST 2002 | wbu
Well Greg, I don�t know YOUR 0805 Pads but if you look at the recommended pattern for 0805 in IPC-SM-782 you might notice that the Z-dimension is somewhat about the size of your 1206 part length. With that and assuming that you ask if the results wi
Electronics Forum | Wed Mar 31 20:34:03 EST 2004 | davef
We have not used this specific package. We agree on your toe fillet idea. Toe fillets add no strength to solder connections. This part is a MicroLeadFrame�, which is similar to QFN, BCC, LGA, and whatnot. Consider: * Searching the fine SMTnet Arch
Electronics Forum | Mon Jul 16 09:04:00 EDT 2001 | Hussman
No argument here. But I've don't think I've ever seen solder balls on 0402s. Even when they're placed on narrow G dimension pads, where there is little toe fillet, I've never seen a solder ball. But your idea of reversed homeplates would work grea
Electronics Forum | Mon Jun 27 09:38:30 EDT 2005 | Bob R.
What problems are the quality people seeing? I hope they aren't expecting a toe fillet. QFNs are typically cut from an array after plating. This leaves exposed copper on the sides of the part. We'll often see smearing from the sawing process that
Electronics Forum | Fri Jul 15 13:58:32 EDT 2005 | seaK
Our production is putting QFN40 and QFN56 package on board. With 80% opening on terminal, 40% on thermal pad, we found QFN56 100% forming toe fillet, but it does not work out the same to QFN40. We suspect it's because of the weight of component.....
Electronics Forum | Thu Jul 05 15:13:46 EDT 2007 | joeherz
We've seen non-functional QFNs cured by touching up the toe fillets. Especially with parts that are not plated on the edge/face where you get minimal/no wetting due to oxidation of bare copper. I'm not suggesting that you touch everything up but th
Electronics Forum | Fri Mar 05 02:59:59 EST 2010 | grahamcooper22
Hi, Do you have a picture on one of these leads where the solder has covered the lead ? As this is a gull wing device I wouldn't expect solder to cover it. I expect to see a toe fillet / wetting around the sides of the lead and a heel fillet. If your
Electronics Forum | Wed Mar 29 22:30:13 EST 2000 | cklau
Hi guys; There are a few points that should be taken in to considerations regarding IPC-SM-782 land pattern and design rules. As a general rule all SMT reflow pattern should be in comply with SM-782 but however for special cases like : * PLCC land
Electronics Forum | Wed Mar 31 13:05:46 EST 2004 | JoeH
Anyone used this package? It's Cygnal PN C8051F300. The part has bottom side, flat terminations (like a BGA without the balls). There is metalization on the sides of the package but it's not plated (bare copper). Metalization on the bottom is pla
Electronics Forum | Tue Aug 22 12:56:29 EDT 2006 | Chunks
Russ is right. The pad in the middle needs to be soldered as well. Also, the ends of leads exposed are not plated as well, so you will never get a toe fillet. Drives our IPC experts nutty, or should I spell it "knutee"? I don�t know, I went to a
