Electronics Forum | Thu Apr 12 01:35:13 EDT 2007 | Haris
IPC-A-610D is a Acceptability of the Electronic assemblies so all your questions depends on the product classes either 1,2,or 3 and it is given in this standard about the acceptablity criteria of the soldering of any type of the components i.e. it h
Electronics Forum | Wed Apr 11 20:49:39 EDT 2007 | raychamp007
3W. Figure 8-84 shown evidence of heel bend wetting(but no written criteria mention about the solder fillet must present at the heel bend). It is acceptable if the minimum D(3W/75%L)extend from toe which is no evidence of solder fillet at heel bend?
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 | Wed Feb 06 17:24:04 EST 2008 | blnorman
We had a vent block up not too long ago ourselves. Saw multiple solderjoints, especially on fine pitch micros, that looked like they had alligator toes. We solder bump, so it was obvious that area didn't get hot enough to liquify the solder and hav
Electronics Forum | Tue Sep 30 14:06:04 EDT 2008 | realchunks
What pitch? You can go 5 mil or even 6 mil stencils depending on your screen printer. Also what do you consider "less solder"? What defect are you having. Remember on a QFP you use the heel filet to determine proper solder joint - not the toe.
Electronics Forum | Mon Aug 22 06:30:59 EDT 2011 | janz
very often toes on the QFP packages are exposed to base material and during time they oxidize. That is why you can have problem with solder fillet. Most important is heel fillet. Regarding your misalignment of IC if this is repeatable check your pl
Electronics Forum | Thu Mar 29 08:28:28 EDT 2012 | williamaxler
In the IPC-A-610E standard QFNs are classified as BTC (bottom termination components). Most QFNs do not have a solder-able surface on the outside of the part. Usually the lead that you can see on the outside is copper and classified is not solder-a
Electronics Forum | Mon Jul 01 13:25:31 EDT 2013 | tpost
I think it is wetted also but I cannot verifiy without actually seeing the toe, heel or side fillets. In this case, the lead was overhanging the pad and as with this type of lead it is not acceptable so they were reworked. Many times rework personel
Electronics Forum | Tue Jul 04 14:50:52 EDT 2017 | dleeper
Thanks! good stuff. I am disappointed the IPC has put off updating QFN solder filet specs till rev H. It's a pet peeve of mine trying to argue with customers that a visible toe filet on a QFN is not necessary, and may not even be possible depending
Electronics Forum | Thu Feb 17 21:42:12 EST 2000 | Dave F
Hey Bud: Moved from that Bi-crap to something serious, eh? Several things: 1 Get in touch with Doug Romm (drom@msg.ti.com) at Texas Instruments. He talks palladium. 2 Review the archives on Palladium. 3 I think you're running light on temps. Eut
