Electronics Forum | Fri Mar 16 17:15:51 EDT 2007 | davef
Ask the board fabricator to: * Fill the vias with resin. * Then metalize and copper plate the filled via along with the pad. * Then plate with solderability protection. This results in what appears to be a solid pad. For more, look here: http://www
Electronics Forum | Sat Oct 12 06:43:49 EDT 2002 | davef
Alternatives to consider are: * Opening-up your stencil aperture put-down more paste to compensate for the amount that is being used to fill the via. * Relaying-out the board to plug and plate over the via. * Relaying-out the board to move the via fr
Electronics Forum | Fri Mar 23 09:13:48 EDT 2007 | Peter W
Hello, those plated and solderable via in pads have two critical points: 1. We have discovered that _sometimes_ the plating seems not to be perfect, as extreme voiding is visible in tha bga solder ball 2. The detection of some defects by AXI is limi
Electronics Forum | Mon Feb 26 20:02:42 EST 2001 | davef
First, I don�t understand why your board fabricator can�t do a good job plugging your vias. Additionally, when you consider that they forgot to plug the first batch of boards, it makes me wonder if they are desirable as a supplier. Generally, we us
Electronics Forum | Tue Aug 31 12:42:45 EDT 1999 | Charles Barker
****************************************** ***************** HELP! *************** ****************************************** We are having a special ceramic smt board made. The boards are 16-up arrays that have smt pads on both sides. Only thre
Electronics Forum | Mon Mar 04 17:52:59 EST 2002 | davef
Yes, providing the surface of the via is solderable. * If so, how much paste? => Vias come in various sizes. Boards vary in thickness. So, the amount of paste to fill a via varies. Roughly, you�ll need twice as much paste as the volume of the via
Electronics Forum | Tue Sep 25 14:08:59 EDT 2001 | davef
Oooo, the solder on the pad and PGA ball is flowing during reflow down the via to the secondary side? Why didn�t you say so?? ;-) Why would you expect that gravity and capillary action wouldn�t force solder to flow down the solder plated via to the
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 | Thu Jan 06 08:03:47 EST 2005 | davef
On solder in vias: It looks like the via are not solder masked well and pick-up solder either: * Solder coating ... OR * During leveling It's possible that the design specifies openings in the solder mask for these via. On solder in the unsupporte
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
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