Electronics Forum | Tue Mar 21 16:25:23 EST 2000 | Boca
Full radius corners on pads can help with solder paste release in the stencil. The radius shape minimizes the surface area in the wall of the stencil aperture as compared to a sharp corners. When the stencil is seperating from the pcb the solder pa
Electronics Forum | Wed Apr 25 10:37:14 EDT 2001 | davef
If you heat a BGA too quickly, the corners of the device will curl towards the ceiling [potato chip], because they come to temperature faster that other areas. Adding to this, thinner substrates tend to potato chip more and faster than thicker subst
Electronics Forum | Tue Jun 15 09:15:16 EDT 1999 | Clifford Peaslee
We moved this message to the admin corner, where I responded, please use admin corner for messages like this. Cliff | I hate to say this because I go into this great forum all the time, but ever since the announcement of "moving to a new and faste
Electronics Forum | Mon Mar 12 08:59:46 EDT 2007 | davef
Questions are: * You say 'voids', but you describe poor barrel fill. Are you seeing both? * Sometimes designers need to reduce the heatsink effect of large ground and power places, but this usually shows on the two upper corner pins, not all corners
Electronics Forum | Tue Jan 22 16:05:51 EST 2008 | jmelson
This is an OUTSIDE corner spec or an inside corner spec? If outside, I don't see why it is a problem, but will require programming the router or making a template (if an "old school" shop.) Yes, if an inside corner, then it requires a small router
Electronics Forum | Thu Sep 15 09:31:02 EDT 2016 | ladmo1
While removing one part, another part - BGA part - several components away, actually melted on one corner - you can see the plastic body of the part oozing out around one corner between the solder balls. Several of the solder balls on the one corner
Electronics Forum | Wed Jun 21 18:51:34 EDT 2000 | John
What is the most likely causes of shorts in the corners of BGA devices?. Is there a method of removing single shorts without removing the device?. John.
Electronics Forum | Thu May 17 07:58:25 EDT 2001 | Bob Willis
I think the answers to the problem have been given but if anyone wants to see this happening and solder shorts forming during corner warp there is a video clips on BGA shorts to download. Its available free on http://www.bobwillis.co.uk It should am
Electronics Forum | Tue May 14 20:58:42 EDT 2002 | davef
Maybe the issue is not a proper rework method. Your shorts on the corners are caused by too fast of a profile causing the corners of the BGA to get too hot, too fast, which made them curl, like tatter chips.
Electronics Forum | Fri Jun 14 14:29:22 EDT 2002 | davef
Russ makes good points. Search the archives for: * Links to rework machine profiles. * Discussion on people causing corner shorts on their BGA, when heating them too rapidly, making the corners to curl like potato [potatoe?] chips.