Electronics Forum | Mon Jan 11 14:48:44 EST 2010 | davef
SR1000 is commonly used for tenting. Search the fine SMTnet Archives on : tenting Someone gave us this note. We have lost their name. It seems to be good advice. If Liquid Photo Image (LPI) solder mask is required, do not tent via holes. Tenting
Electronics Forum | Wed Jun 01 00:25:28 EDT 2011 | alcatel
I have one pcb which has via holes on both solder pads of 0402 chips. Right now im using type 3 solder paste with 45 degree squeegee. and a lot of these chips are tombstoning. Im guessing with larger particle size of solder paste, the solder will
Electronics Forum | Wed Mar 23 22:29:21 EDT 2011 | nkinar
I have a few prototype circuit boards with BGA footprints where some (but not all) of the vias have been placed too close to the pads. During reflow, some of the solder from the balls flowed into the holes. Only one of the pads under the BGA is not
Electronics Forum | Thu Jun 02 10:54:12 EDT 2011 | davef
Al: We agree with AVFOM. You have a different problem than solder paste mesh selection. Most often, tombstoning occurs when the wetting forces on the two pads are unequal. Examples of things that can cause this are: * Pads are different * Board pad
Electronics Forum | Thu Jun 02 07:27:11 EDT 2011 | scottp
You need to post a picture or describe your geometry better. Is this a through hole via in pad or is the via offset from the pad with no soldermask in between?
Electronics Forum | Thu Jun 02 06:23:08 EDT 2011 | alcatel
1 chip has 2 solder pads....and both pads definitely has solder.... im not getting what you are trying to say.
Electronics Forum | Thu Jun 02 06:23:40 EDT 2011 | alcatel
1 chip has 2 solder pads....and both pads definitely has solder.... im not getting what you are trying to say.
Electronics Forum | Wed Jun 01 14:50:09 EDT 2011 | kahrpr
Try shifting the placement location slightly toward the pad that is not soldered. This is assuming it is always standing up on the same pad
Electronics Forum | Thu Mar 24 16:53:53 EDT 2011 | davef
Can you jumper the via to the pad?
Electronics Forum | Thu Mar 24 18:05:54 EDT 2011 | nkinar
That's really interesting, davef. How would I jumper the via to the pad? Could you elaborate?
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