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Mail Archives: geda-user/2019/03/21/17:00:47

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From: "John Griessen (john AT ecosensory DOT com) [via geda-user AT delorie DOT com]" <geda-user AT delorie DOT com>
Subject: Re: [geda-user] Modify SMD stencil aperture size to prevent short
circuits?
References: <999a6a2b-c727-4f22-3aaf-b6c20cf15807 AT linetec DOT nl>
Message-ID: <e6ee6566-03f2-3082-9fbe-4fe3f4464ae7@ecosensory.com>
Date: Thu, 21 Mar 2019 20:58:50 +0000 (UTC)
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On 3/21/19 6:01 AM, Richard Rasker (rasker AT linetec DOT nl) [via geda-user AT delorie DOT com] wrote:
> After some searching, I found that decreasing the size of the openings in the stencil and thus the amount of solder paste ending 
> up on the PCB appears to be a common way to prevent shorts of this nature.
> 
> Can anyone confirm that this is indeed a good idea? It

Here is what I got some shorts on, but could fix with reflow a 2nd time:

https://www.cibolo.com/docs/pyflex_f401_assy_v0.5-7.jpg

this paste pattern was too much paste:
https://www.cibolo.com/docs/UFQFN48-subc-2.png

This pattern works better:
https://www.cibolo.com/docs/pyflex_f401_QFN_footprint-1.png
https://www.cibolo.com/docs/pyflex_f401_QFN_footprint-2.png

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