Electronics Forum | Wed Aug 09 16:30:43 EDT 2000 | MarkS
Has anyone had (successful) experience placing testpoint vias under BGAs? We already have conventional vias, but we're contemplating converting them into testpoints (probably by enlarging the bottom-side copper diameter to .036" and opening the bott
Electronics Forum | Wed Aug 09 22:11:46 EDT 2000 | Dave F
Mark: The best routing of test vias for BGAs is to keep them far away from the device. We route test pads for the outer two rows of balls and use vias as test pads for the inner rows of balls. Your bottom-side layout is fine. Yes, on the top-side
Electronics Forum | Thu Apr 11 19:06:59 EDT 2002 | tmarc
We are using 1mm pitch BGAs with a great quantity of via(s) under the component. Very shortly we will be placing CSPs with .65mm pitch. Our via(s) are solder masked, however we generally have a percentage of them that the masking is thin enough that
Electronics Forum | Fri Jun 07 09:50:13 EDT 2019 | teejsd
Closer pics at angle would seem to support soldermask delam. And I am now wondering if our no clean flux is getting properly inactivated where it is sitting under the mask.
Electronics Forum | Fri Jun 07 11:10:08 EDT 2019 | teejsd
We also have a Foresite C3 for spot testing for ionic contamination. I didn't use it at this spot, but used it some other spots around the PCB that showed this color change and with our C3 we were passing IPC standard for ionics. But I was wonderin
Electronics Forum | Mon Feb 06 10:02:14 EST 2006 | Yash Sutariya
Sorry. I actually should clarify those slides. Black pad is not associated with tented vias. Also, you can tent vias with soldermask, but this requires the immersion gold process to be completed prior to soldermask. As such, all copper features (
Electronics Forum | Thu Sep 01 11:25:21 EDT 2005 | chunks
Unless it is peppered with via holes. Then it depends on the size of the pad and via holes.
Electronics Forum | Sat Jul 16 13:53:52 EDT 2022 | yannick_herzog
Hello all, we use a reflow oven from Rehm in our SMT production. At the moment we solder under nitrogen atmosphere (approx. 500ppm). Now we want to reduce the nitrogen consumption (costs etc.). What consequences can occur here? Especially on the s
Electronics Forum | Mon Jul 02 10:44:14 EDT 2012 | mccabekev
We are applying a SR conformal coating via aerosol. Both permanent marker and paint pen are running as soon as the spray hits it
Electronics Forum | Tue Nov 13 20:29:03 EST 2007 | grantp
Hi, What size via's are you guys seeing, as the ones in our products are incredibly tiny, and via's are very small now days. The via's on the boards we have are dramatically smaller than the pad on an 0402. Grant
