Electronics Forum | Tue Jun 28 21:54:44 EDT 2005 | davef
Fabricators take different approaches in developing paste that is more or less prone to solder balling. That being said, you should be able to overprint 250 thou, no problem. Prove this to be correct by printing paste on a scrap board with an obsol
Electronics Forum | Wed Jul 13 12:27:40 EDT 2005 | Bob R.
Are you seeing solder balling on your discretes when you print 1:1? Are you washing your boards?
Electronics Forum | Sun Sep 04 23:42:31 EDT 2005 | juan2208
hi all, i have a question about the wirebonding That is under what circumstances that the ball bonding is used and under what circumstaces the wedge bonding is used? thanx advanced.
Electronics Forum | Fri Oct 07 09:19:54 EDT 2005 | Kris
the direction in which the solders cool in a BGA are also different than the rest of the boards as the joints " hidden" to ambient. Refer to an analogus phenomenon in the cookson application note. http://www.cooksonsemi.com/pdfs/How%20&%20Why%20Bum
Electronics Forum | Thu Sep 29 20:26:58 EDT 2005 | DasonC
Any aperture/stencil thickness suggestion to provide a rigid solder joint for 0.8mm pitch PBGA with 0.4mm ball diameter. The pad is based on IPC7095 and it is 0.3mm. Thank!
Electronics Forum | Wed Oct 05 15:31:44 EDT 2005 | chunks
Thanks Amol, You brought up some good ideas that we'll use. Has anyone ever heard of under filling the BGA (after reflow) with a material that cures, then thermal removing the BGA to check the acual size of the ball to pad?
Electronics Forum | Wed Nov 23 07:39:14 EST 2005 | chunks
Shorted to the sheild or the BGA balls are shorted? Sheilds move a lot during reflow. If this is the case, place some adhesive or peelable solder mask on either side of the shield and baords to stop it from moving.
Electronics Forum | Thu Jan 05 12:26:20 EST 2006 | Rob
The larger BGA's can also warp more under higher temperatures which causes ball lift, more noticable towards the edges of the package.
Electronics Forum | Fri Dec 02 02:35:51 EST 2005 | grantp
Hi, I have always wondered about these scopes and are they any good? They seem expensive when you consider you really only see the outside balls, and with small lead-less parts becoming more common, would the money be better spent on a good X-Ray?
Electronics Forum | Mon Dec 05 09:22:34 EST 2005 | russ
I'm sure that we have all seen it but it can be from so many different things. Definitely can be from flexing, Are you 100% sure that they are good prior to this install remove process?
