Electronics Forum | Tue Mar 31 08:11:51 EDT 2009 | davef
Solder ball formation can be a significant problem if the balls get trapped in the smaller spaces between ceramic chip carriers and substrates or possibly between the leads of small pitch leaded ICs. The solder balls also reduce the solder volume ava
Electronics Forum | Fri Feb 19 14:43:46 EST 1999 | Nithy
We are in the process of getting into no-clean paste and fluxes. One important issue in this is sodler balling. I have heard some people say that having a matte finish would help in having lesser solder balls and that the solder balls would not be
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 | Tue Jun 04 11:14:48 EDT 2002 | ckd
Hi All - My question is how do solder balls form and stay in the vias? The assembly goes thru SMT top placement, reflow then thru hole components mounts on top side as well. The board is sent thru the wave solder process. Has anyone experienced this
Electronics Forum | Mon Dec 02 17:02:28 EST 2002 | Vince Whipple
Steve, I agree with the recommendation to check the temperature. This is the first place to go. Is this an IPA or water based Noclean? What is the topside temp of the assembly at the effected areas? If you are too cold you will have a tendency to hav
Electronics Forum | Tue Apr 27 12:01:10 EDT 2004 | Dreamsniper
Hi, Can anyone help me as to what is acceptable and reject when it comes to solder balling under BGA's? I've got some BGA's with solder Ball but they seemed to be attached and they are about 10% of the size of the actual soldered BGA joint size. Our
Electronics Forum | Tue Jul 06 10:46:12 EDT 2004 | blnorman
We have now switched to Kester EP256. During our solder paste evaluation, resistance to humidity was one of the selection criteria. We printed multiple boards, then exposed them to 85�F/65% RH. At 30 minutes, 1 hour, 2 hours, and 4 hours exposure
Electronics Forum | Mon Nov 15 14:24:17 EST 2004 | nrocco
Im looking for equipment that can attach solder balls between the size 15-25 mils to the leads of a land grid array. There is also the posibility of attaching balls before leads are inserted into the socket. This is a little differant than attaching
Electronics Forum | Sun Jun 12 19:22:52 EDT 2005 | techknow..
When examining a Bga using an Ersascope, I found that all the joints where good. However I found that the first few solder balls from left to right ( vice versa ) seem higher than the middle solder balls. It appears that the body of the part is flex
Electronics Forum | Tue Jun 06 11:57:12 EDT 2006 | Chunks
IPC 610 says acceptable Class 1 (Class 2, 3 indicator) if they are entrapped/encpsulated balls within 0.13mm of lands or pads. or exceed 0.13mm in diameter. Defect Class 1,2,3: Solder ball violates min electrical clearance. Solder balls not entrap
