Electronics Forum | Wed May 12 07:53:28 EDT 2004 | solderpro
Lets make it easy on the poor guy, some are correct, check you profile but remember one thing most do not apply, it is important to match the type of paste you are using with the style of oven and configuration. send a direct email and I will give so
Electronics Forum | Tue Jul 17 15:13:53 EDT 2001 | mparker
Dave - I agree that the U shape for QFP's sounds a bit whacked, for the reasons you state. It may work OK for larger pitchs but then again there are a myriad of fixes that work before resorting to U shapes. With the U shape removing paste from under
Electronics Forum | Wed Jul 06 06:17:11 EDT 2016 | pavel_murtishev
Dear members, Recently we have found that solder mask thickness variation could lead to solder balling under QFN packages for a high reliability device. Is there any industry proven method for solder mask thickness checking? Any equipment or any me
Electronics Forum | Fri Sep 21 14:03:45 EDT 2001 | jschake
I have observed solder balling for all aperture sizes tested. Solder balling levels appear to be better correlated against the amount of solder paste that is underneath the 0201 component terminations after placement rather than comparing this to th
Electronics Forum | Thu Aug 10 03:30:42 EDT 2000 | JohnW
Ramon, Solder ball' are a bitch aint they?, identifying the right location to fix em is a bigger one. As you and the rest of teh guy's have said yes you'll need to look at your stenil..but maybe your stencil is good so you'll need to look else where
Electronics Forum | Mon Aug 07 10:22:13 EDT 2000 | genglish
Ramon, I have had experience in the problems you are witnessing. The problem can relate to a number of factors. Obviously the printing process is the first place to start your investigations, try looking at the stencil apertures for bleed under the
Electronics Forum | Thu Aug 10 13:16:17 EDT 2000 | Bob Willis
Here is some thing that I wrote a while back on solder beading. First what is a Solder Bead? The term solder bead is used to differentiate it from solder balls. A solder bead is a solder ball but its location is normally constant unlike solder bal
Electronics Forum | Thu Oct 26 08:59:56 EDT 2000 | Antonio A. Medina
Ok guys, I need help. Here's the deal. We're getting micro solder balls under discreets on the bottomside of the board. Here's my set up... MPM screener w/vacuum plate 6 mil metal screen with 90% circular (rounded) apertures 7 mil (measured) past
Electronics Forum | Fri Apr 29 07:14:13 EDT 2005 | jdumont
Recently we have been seeing issues with an inability to print through .45mil apertures on our stencils. We have also been seeing a alot of solder balls under some BGAs (some worse than others). I was checking the refridgerator (small mini fridge) we
Electronics Forum | Tue Jun 07 08:31:57 EDT 2011 | bootstrap
I am building a rugged digital video camera product that essentially is just a sandwitch of 3 parts: #1: front piece is machined aluminum with C-mount thread #2: middle piece is 1/16" printed circuit board #3: back piece is machined aluminum The