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Mail Archives: geda-user/2015/07/27/08:09:33

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Date: Mon, 27 Jul 2015 14:09:52 +0200 (CEST)
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To: "Gabriel Paubert (paubert AT iram DOT es) [via geda-user AT delorie DOT com]" <geda-user AT delorie DOT com>
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From: gedau AT igor2 DOT repo DOT hu
Subject: Re: [geda-user] high freq, trace lengths (was: pcb-rnd feature poll:
please vote)
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On Mon, 27 Jul 2015, Gabriel Paubert (paubert AT iram DOT es) [via geda-user AT delorie DOT com] wrote:

Thanks for the details!

I have one question about stubs.

> In both cases:
> - these are point to point signals and stubs are essentially prohibited,

http://nxp.com/documents/application_note/AN10935.pdf

fig 4 on page 9 shows how two DDR rams connected to a single MCU. There 
are regular T junctions there. I guess with proper trace 
lengths/impedances/termination this should be possible.

I've seen such topology (in application notes) before, that made me think 
the best would be to calculate lengths independently on all the three arms 
of the T. Does this idea make sense?

Regards,

Igor2

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