Electronics Forum | Wed Nov 14 13:05:40 EST 2007 | rgduval
I had one project with micro-vias in 0805 and larger pads, with no issues. But my most recent project had vias that were larger than the 0402 pads that the via was in. To the point that for a number of the lands, there was no visible pads (a couple
Electronics Forum | Wed Nov 21 15:02:46 EST 2007 | jlawson
From info I have been told from design standpoint, via in pads helps with managing EMC issues with working design, in particular for high speed digital/dense populated type PCB's. We had a manufacturing customer that had very low yield because of th
Electronics Forum | Tue Sep 25 12:49:58 EDT 2001 | Hussman
Been there - done that. Makes a mess on that 2nd reflow process- doesn't it!?!?!? This is caused by design. If the open via is located in the land area, it will flow thru the via and cause pumps on the opposite side. You can have your vias filled
Electronics Forum | Mon Nov 05 02:51:48 EST 2007 | omidjuve
our boards have many smd pads that has vias under them so when the screen printer wants to print the solder paste on it , it will penetrate through the via to the bottom side of the board and cause many problem for us . i want to know that is it sta
Electronics Forum | Mon Mar 04 11:08:56 EST 2002 | Matt Kehoe
We have a customer that desires to have their via holes plugged with solder after assembly. Is it possible to add the via holes to the stencil and print paste into them and expect them to plug? If so, how much paste? One to one on the stencil opening
Electronics Forum | Mon Nov 05 06:27:23 EST 2007 | grantp
Hi, We are also interested in this, and I have heard you can get the PCB's with the via's plugged. Also, if the via's are small, the solder should not penetrate? Anyone have any further info? Grant
Electronics Forum | Tue Nov 20 12:31:12 EST 2007 | kelz
In my past experience, having via's under or attached to SMD lands produces risk. Solder will not consistently wick the same if it is being drawn into a via. This has also caused issues from solder wetting through the via to the other side causing a
Electronics Forum | Fri Nov 23 15:46:06 EST 2007 | mika
Question: We have an issue right know on a prototype batch with via in the pad on an very small pcb 50x50mm (in a panel of course). The designer has no room to move the vias as they said. The pcb is to packed with components also 8-layers. It is also
Electronics Forum | Fri Nov 23 16:32:05 EST 2007 | davef
There a several things you can do to prevent the solder wicking down the hole with the current design, and that's where you should focus. Cost goes up as you go down the list, but in neither case do you need to respin the board, have solder starvatio
Electronics Forum | Tue Mar 05 22:34:27 EST 2002 | YoYo
You better be careful how you plug vias at screenprint - we currently have a customer that wants vias plugged, so we had a 2% aperature reduction so we would not have to much paste, I believe it should have been reduced more because some of the solde
