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Message-ID: <1405875320.394.9.camel@pcjc2lap>
Subject: Re: [geda-user] opper ring flag for vias and pins
From: Peter Clifton <pcjc2 AT cam DOT ac DOT uk>
To: geda-user AT delorie DOT com
Date: Sun, 20 Jul 2014 17:55:20 +0100
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On Wed, 2014-07-16 at 14:22 -0400, DJ Delorie wrote:
> > You need to be able to remove inner layer pad annuli completely for 
> > signal integrity reasons on some high-speed lines.
> 
> Aren't there manufacturability issues if you do that?  I.e. voids
> where the copper should be, causing breaks in the barrel?

Apparently not.. I've seen it recommended for a number of high-speed
applications now. I guess the pre-preg resin fills the void? (Or if not
completely - that it does enough for plating to succeed).


--
Peter Clifton <peter DOT clifton AT clifton-electronics DOT co DOT uk>

Clifton Electronics