Electronics Forum | Thu Feb 05 05:27:55 EST 2004 | dszeto
We have recent customer asking for PCB's PTH hole size related to soldered wire AWG 18-26. Please kindly advise any international standard for captioned issue. Thanks!
Electronics Forum | Thu Feb 05 08:39:16 EST 2004 | davef
IPC-2222 - Sectional Design Standard For Printed Board For Organic Printed Boards, Table 9-3 � Plated Through Hole Diameter To Lead Diameter Relationships will give you the standard information you require.
Electronics Forum | Thu Oct 31 02:43:55 EDT 2013 | hqew2013
The smallest finished hole available for 2 layer board is .020”. The smallest finished hole available for 4+ layer board is .014”. All holes are round and drilled through from top to bottom layer of board. No blind or buried vias. For holes = .15
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 | 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 | 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 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 15:50:59 EDT 2011 | markhoch
I don't believe that particle size of the solderpaste will offer you any relief from this issue. The solder flows into the via, leeching away from the desired solderpoint, after the solder has become liquious. The chemical make-up of the solder contr
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
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