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	Wed, 17 Sep 2014 03:03:52 -0700 (PDT)
Date:	Wed, 17 Sep 2014 11:03:52 +0100
Message-ID:	<CAD2FfiFD7ku0pJAooDPpXjiKJrSEvjfMYoPt9fjNskqdeTF55g@mail.gmail.com>
Subject:	[geda-user] Surrounding a component with an island of non-ground
From:	Richard Hughes <hughsient AT gmail DOT com>
To:	geda-user AT delorie DOT com
Reply-To:	geda-user AT delorie DOT com

Hi all,

I'm designing a double sided PCB that has two giant rect acting as a
ground planes on both sides, with traces hand-drawn for the signals.
This works well from an EMI point of view for the digital logic on the
board. I'm now adding a photodiode array and 24 bit ADC (down to 20nA
input current) , and want to surround all the signal traces from the
array to the ADC in an island of common cathode, to avoid any leakage
currents.

I'm able to join traces to the ground plane using "j", but I'm not
able to work out how to "join" an island of a polygon to a random
signal. I guess I'm trying to ask how to "join" random lines with
random polygons, without drawing a complex digital ground polygon
around the photodiode array. Ideas very welcome, thanks!

Richard

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