Electronics Forum | Wed May 26 14:14:17 EDT 1999 | Parvez Patel
hello all, I was just wondering, Is it true, that for a given package (area array), upto a certain limit, the assembly reliability improves with decreasing land pad diameters? Thankx in advance Parvez Patel Graduate REseacrh Associate SUNY-Binghamt
Electronics Forum | Wed Apr 27 07:16:40 EDT 2005 | jdumont
Thanks a lot guys. The part dims are in mm by the way. So last night i was looking at the .pcb file and saw that the pad size and stencil are both .013" while the ball on the BGA is .018" (sorry for switching from metric). Is this ok or can i have en
Electronics Forum | Wed Apr 27 12:26:49 EDT 2005 | jdumont
Square you say? Wouldnt this give less paste deposition than a circle and basically reduce the standoff height the same as making the pad bigger? Would using a type 4 paste for this size stencil aperture (.013") be a good idea? Thanks JD
Electronics Forum | Wed Apr 27 13:17:14 EDT 2005 | grantp
Hi, That was one of the recommendations made when I had the problem, but I never followed it up. Would the outside corners of the square aperture be on the edge of the pad, so you would be putting down less paste on a smaller aperture, but it's sq
Electronics Forum | Wed Apr 27 10:47:26 EDT 2005 | HOSS
A 1:1 pad to ball diameter will cause the balls to collapse more giving you less post solder component standoff. Depending on the application of this product and required reliability, you may want to stay with the padstack being used. You may try c
Electronics Forum | Tue Apr 26 16:00:08 EDT 2005 | jdumont
Good day all, we are having problems with some new BGAs that are slowly filtering their way into our designs. Engineering really wants to use them and I am pressured to make them work. They are 54 ball BGAs. The pitch is .8 mils and the ball diameter
Electronics Forum | Wed Apr 27 02:22:08 EDT 2005 | grantp
Hi, There are a number of things you can try. You are already using 1:1 hole to pad ratio, and that's good as you need the size. I would try an electroform stencil as that will have a smooth side of the aperture and help paste release. Don't use c
Electronics Forum | Thu Nov 14 10:52:56 EST 2019 | jandon
Maybe something like this could work?
Electronics Forum | Wed Jun 23 18:23:32 EDT 1999 | Tom B.
Even though you may find a pad-pad thru-hole spacing, part body size, orientation, and insertion head tooling clearences may be the deciding factor in spacing. 1. Part body diameter will dictate component centroid spacing. ---[][][][
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.
