Electronics Forum | Tue Jan 08 09:23:18 EST 2013 | lock_2002
This is a question regarding soldermask between pins of fine pitch devices. The majority of our production designs end up with at least 2-3 mils of copper thickness on the external layers due to blind vias, wrap plating requirements, etc. Our curre
Electronics Forum | Wed Sep 18 18:48:33 EDT 2002 | davef
Fabs can produce a solder mask web between 20 pitch leads, but I've never seen a web for 16 pitch leads. Although, I would like know a supplier that can lay-down a fine web. Minimum solder mask web width is about 0.004 thou. An absolute mininum o
Electronics Forum | Tue Jan 15 10:53:18 EST 2013 | boriskilk
We wouldn't advocate extending the soldermask beyond the component body but yes to ganging for fine pitch. To ensure we don't run into issues with flaking our preference is not to add solder mask when the space between pins is less than 6 mil.
Electronics Forum | Sat Sep 06 03:48:29 EDT 2008 | rameshr
hai, we r using type 4 solder paste in our pcb assembly process - we are now facing the following problem. 1. two component pads soldering was seemed uncoalesced soldered joint except all the other components. 2. what will be the problem & solution f
Electronics Forum | Wed Sep 10 12:39:58 EDT 2008 | patrickbruneel
Am glad we got that straight There is a big difference between the �real world� and the �ideal world�.
Electronics Forum | Mon Sep 08 01:45:35 EDT 2008 | rameshr
1.The Temperature on the pad is 247.C & also it is an lead free profile, the same profile we have used till last lot but we had obsereved this problem earlier to this current batch. 2. Both in Type3 & Type 4 paste we are using because of we are using
Electronics Forum | Thu Sep 11 09:59:47 EDT 2008 | rarnold
Paste stored tip down, so separation in the tube is not suspect. Remember that the defect was produced on a screen printer running with a Rheopump. A few more details are that the strip of the board containing the uncoalesced solder is consistent w
Electronics Forum | Mon Aug 16 04:47:04 EDT 1999 | Charles Stringer
| | | One of the DFM suggestions I've seen is to remove the solder mask web, i.e. the mask between pads on 20-mil QFP devices. The rational is that if the mask is thicker than the pad the mask can prevent the stencil from making intimate contact wit
Electronics Forum | Mon Aug 16 07:54:05 EDT 1999 | Peter Barton
| | | | One of the DFM suggestions I've seen is to remove the solder mask web, i.e. the mask between pads on 20-mil QFP devices. The rational is that if the mask is thicker than the pad the mask can prevent the stencil from making intimate contact w
Electronics Forum | Wed Aug 18 21:03:41 EDT 1999 | Dave F
| | | | | One of the DFM suggestions I've seen is to remove the solder mask web, i.e. the mask between pads on 20-mil QFP devices. The rational is that if the mask is thicker than the pad the mask can prevent the stencil from making intimate contact
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