Electronics Forum | Mon May 10 16:37:01 EDT 2004 | davef
First some definitions, the two main types for solder masking near BGA pads are: 1 Pad, Non-Solder Mask Defined. In circuit board design, pads with spacing that does not allow solder (usually bumps) on the pads to contact the adjacent solder mask. [
Electronics Forum | Thu Jun 19 21:39:31 EDT 2008 | mika
Hi, we used to have a RoHS package with uBGA 380 Solder ball's 0.8 mm pitch approx 15x15 mm, bump size is 0.4mm on a 0.33mm pad. Suddenly we need to use another vendor for various reasons. However, the new bump size is 0.45mm according to specs and t
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 | Fri Sep 30 10:07:44 EDT 2005 | davef
Alternate explanations are: * Your reflow profile needs to be tweeked. * Bumps under a die look different than elsewhere on the package. Severe creases may indicate a problem, but creases of only a 0.001 to 0.002" deep should not pose any difficulti
Electronics Forum | Fri Apr 29 17:49:22 EDT 2005 | Woodsmt
I have used many of these devices recently and have used them several times over the last few years. I have been successful using a type 4 paste on a 5 mil stencil. The 13 mil round aperture should provide you with an area ratio just adequate for r
Electronics Forum | Fri Apr 29 17:49:26 EDT 2005 | Woodsmt
I have used many of these devices recently and have used them several times over the last few years. I have been successful using a type 4 paste on a 5 mil stencil. The 13 mil round aperture should provide you with an area ratio just adequate for r
Electronics Forum | Fri May 26 21:25:52 EDT 2006 | mika
Yes we do place "big and heavy" SMT DC/DC:s on most of our board's. Please tell us what brand it is or at least what the package look like?!? For instance we place a different numbers of "heavy" DC/DC converters (40x20mm & 45x25mm) that has the pick-
Electronics Forum | Wed Nov 11 10:08:38 EST 1998 | Magnus
| | Hi, | | We are having problem with yield loss due to electrical fail. Further investigation shows that the failure is due to solder bridging under BGA. Has been there any study or experience on how this could occur and what we can do to prevent
Electronics Forum | Wed Apr 04 18:27:53 EDT 2007 | Guest
Most CSPs are BGAs. Some are sent without bumps or balls. Thjos eneed to be bumped prior to processing for best results
Electronics Forum | Tue Jan 31 13:55:56 EST 2006 | samir
Anyone know what the general rules / requirements are for micro-BGA's and CSP's as to when capillary underfill is required? (ie size of bump/ball, package thickness, PCB/CSP thickness ratios, etc).
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