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Date: Thu, 27 Feb 2014 15:28:19 -0500
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Subject: Re: [geda-user] Via under a pad?
From: Jason White <whitewaterssoftwareinfo AT gmail DOT com>
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Precedence: bulk

I am no expert, so take this with a grain of salt.

In many cases its fine, with BGA's and other fine pitch devices there
is not much of a choice. I have seen it done on many, many high
density boards. I can imagine potential issues with dry joints if
excessive amounts of solder flow down through the via. However, that
only really should become a factor when a) the volume of the via
becomes a significant portion compared to applied solder paste or b)
area of exposed TH plating of the via becomes significant in
comparison to the pad. As you hint at the via of will exhibit a
tendency to become filled with solder but for small "mico-vias" it
really shouldn't matter much at all.

On Thu, Feb 27, 2014 at 3:01 PM, Rob Butts <r DOT butts2 AT gmail DOT com> wrote:
> Is it bad practice to put vias under pads?  These pads are twice as big as
> the vias.
>
> Just curious.



-- 
Jason White