Electronics Forum | Thu Sep 05 03:23:14 EDT 2002 | manic
Hi, I encountered a problem with pbga. One edge either warp downwards or upwards creating bridging or open. This pbga have fr4 at the bottom (compound molding at the top). The fr4 is bigger than the top compound by 3mm at each edge. Pls help. Than
Electronics Forum | Sat Mar 24 05:25:07 EDT 2007 | mika
Thanks aj, Ohh I wish that there was a way to post a picture in this forum or a possibility to attach the datasheet... Which BTW does not have any recommendation of "how to". This package does not have the "center thermal pad" like a QFN or MLF pack
Electronics Forum | Mon Nov 01 10:29:13 EDT 2010 | scottp
I've searched the archives and maybe my search skills aren't up to snuff but I couldn't find much. I'm curious what people are doing for 0.4 mm pitch BGAs, assuming a type 4 paste. Pad diameter? SMD or NSMD? Stencil thickness? Aperture diameter? Us
Electronics Forum | Tue Nov 12 00:49:37 EST 2019 | myke03o
I am optimizing a stencil opening for BGA with 0.4mm pitch and pad diameter of 0.2mm. Can anyone advice of stencil thickness and stencil opening I can use in order to have a good paste release. Thanks for all your answers.
Electronics Forum | Thu Nov 14 10:52:56 EST 2019 | jandon
Maybe something like this could work?
Electronics Forum | Thu Nov 14 18:25:07 EST 2019 | myke03o
Hi Jandon, Thanks, I will try it on my DOE.
Electronics Forum | Thu Nov 14 21:47:41 EST 2019 | sssamw
Yes, 0.25x0.25 square could work @0.1 thickness, use nano-coating or electroform stencil for better solder paste release.
Electronics Forum | Thu Nov 14 22:24:43 EST 2019 | dman97
Use a type 5 solder for maximum paste release.
Electronics Forum | Tue Sep 10 08:22:36 EDT 2002 | davef
I doubt that the interposer is FR4, it's more likely to be BT. Warp during reflow is a function of material a reflow recipe. Your ramp is too fast and is causing the interposer to bend like a potato chip.
Electronics Forum | Tue Sep 07 22:15:26 EDT 1999 | NAZEEH CHAUDRY
| | | I have a zevatech 570 and 560 my boss want to place bga.s with these machines, Ive told him he needs to ugrade to newer machines. Zevatech say "no problem our machine are number 1". | | | these machines dont even offer bga selections. These mac
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