Re: Eagle: via inside a pad, is it possible?

From: Hal Murray (hmurray_at_suespammers.org)
Date: 12/07/04 

Date: Tue, 07 Dec 2004 17:19:17 -0600

>My question was (I think) simpler: I don't seem to be able to make Eagle
>pickup on the vias placed inside the pads; they just seem to be ignored by
>the router. I'm not sure if it's a principal problem, and vias are just
>not expected to be inside the pads or I'm just not setting the router
>correctly. Honestly, I would not even know which setting would I have to
>play with to make it recognize the vias.

I haven't tried it.

I'd expect it to work if you built a special package that had
a pad and via touching eachother. The via would be a normal
through hole via. You would probably have to connect that pin
on the schematic to both the SMT pad and the via. After that,
I'd expect the router to notice that they are connected and
finish things by conecting the via to the right plane or
routing a trace to it.

If you are manually adding vias to an existing layout, you
need to connect the via to that net. (Should give design
errors if you don't and put it in the middle of a SMT pad.)

If you don't make that connection, then the new via is part of
a new net (or something like that) and the router will wire
it to anything else on that net. 

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