Electronics Forum | Fri Jan 22 16:03:17 EST 2021 | SMTA-64387124
Does anyone see any issues in mixing SMD and NSMD pads within one BGA footprint. We have high current pads which we want to make SMD and the other signal pads to be NSMD
Electronics Forum | Tue Jun 02 21:27:22 EDT 2009 | davef
We've never heard of a situtation where oversized pads caused voiding. Your supplier is correct that the pads on the board should be the same size as the pads on the interposer, but this is to improve reliability issues. Search the fine SMTnet Archi
Electronics Forum | Thu Jun 04 20:06:30 EDT 2009 | davef
Since posting the above comment extolling the virtues of NSMD pads and disparaging SMD pads, we've learned that the points apply to all array devices, but in spite of that some designers of fine pitch [eg, 0.4, 0.5mm pitch] array devices choose SMD w
Electronics Forum | Mon Nov 30 08:39:05 EST 2015 | spoiltforchoice
http://blog.screamingcircuits.com/2010/09/smd-vs-nsmd.html such as this? Which handily also tells you what you might want to google.
Electronics Forum | Mon May 28 17:43:33 EDT 2001 | davef
Does this device have a integral heat sink / metal slug on top, like a TI TM320C6XXX er a Altera EP20K4XX? Compare the size of the pads on the interposer and the board. Compare the type solder mask [NSMD vs SMD] on the interposer and the board. Wh
Electronics Forum | Thu Sep 06 05:25:38 EDT 2018 | spoiltforchoice
I'm no expert but I think you will find the majority of discussions around BGA & good printing results focus on the PCB design and things like tented vias and pad definition. e.g https://macrofab.com/blog/bga-pad-creation-smd-nsmd/ After that, work
Electronics Forum | Thu Feb 24 13:28:31 EST 2000 | Dave F
Robert: Ah, opinions are like mothers, everyone has one. Here's mine: 1 Goto the Altera site, get a copy of "AN 114," follow it. Generally, manufacturers are closer to the requirements of their components than others are. 2 Metal showing on the b
Electronics Forum | Thu Feb 24 13:28:31 EST 2000 | Dave F
Robert: Ah, opinions are like mothers, everyone has one. Here's mine: 1 Goto the Altera site, get a copy of "AN 114," follow it. Generally, manufacturers are closer to the requirements of their components than others are. 2 Metal showing on the b
Electronics Forum | Thu Oct 25 13:35:47 EDT 2012 | davef
Here's a paper that may help http://www.ipcoutlook.org/pdf/assembly_challenges_bottom_terminated_ipc.pdf Temperature Impact * Profile didn’t have a significant impact on voiding. * Voids slightly increased with higher temperature. Reflow Atmosp
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
