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Message-ID: <4F61DF38.2010001@penguindevelopment.org>
Date: Thu, 15 Mar 2012 13:23:20 +0100
From: Link <link AT penguindevelopment DOT org>
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To: geda-help AT delorie DOT com
Subject: Re: [geda-help] Query : Tracks On Both Side
References: <CAF0dY_uOGCB4h+SsgUCap0MvHtS9Oz8tafAeg9AJpQXiJ_4sog AT mail DOT gmail DOT com>
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Reply-To: geda-help AT delorie DOT com

On 15/03/12 10:24, chetan patil wrote:
> Hi,
>
> I'm designing a PCB which will have ICs with SO package and other
> electronic components
> will be through hole. Till now whatever design I did they had DIP ICs
> and through hole components
> so it requires just one side design of PCB.
>
> However now, how should I proceed for designing SO package with through
> hole such that
> SO package ICs tracks are on top and rest are at bottom.
>
> May someone give me starting tips for designing two sided PCB as I'm
> considering my task will come
> in same.
>
> --
> Thank You and Warm Regards,
>
> Chetan Arvind Patil,
> www.chetanpatil.info <http://www.chetanpatil.info/>
>
>
>

You can just put most signal traces on the top layer. If you have 
through-plated vias, putting the solder on the bottom layer creates an 
electrical connection to the top as well. If you don't have 
through-plated vias (e.g. because you're make the boards yourself), you 
can either manually solder the pins to the top layer, or for components 
where you can't reach the pin on the top layer, use a short trace on the 
bottom and bridge it to the top by soldering a small length of wire into 
a hole. If you have a simple layout, you may even be able to get away 
with only having copper on the top side of the board (it's kludgy, but 
not impossible).

If you do use two layers, it's probably best to use the bottom layer 
mostly as a ground plane and for anchoring the through-hole pins, 
keeping the signals on the top layer.


Peter