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Re: gEDA-user: trace routing "style" in PCB



Wow !  Blast from the past.  I thought nobody answered.

My question and basic goal remains unsatisfied.  And the example below from
Xtian Xultz is right on point.

I want to annotate/tag wires on the schematic with information to control
the trace width.
This needs to be done more finely than at the net level, as not all portions
of the same net need to carry same amount of current.

I have done this sort of thing with Protel.

I get the feeling that gschem/pcb do not have the infrastructure needed to
support this kind of feature.

Regards,
Bert Douglas


> Delivery-Date: Wed, 27 Oct 2004 12:06:41 -0400
> From: Xtian Xultz <xultz@xxxxxxxxxxxxxxx>
>
> I dont think it is a good idea.
> Imagine a switched power supply, with a flyback. At the output of the
> transformer, you have some diodes and capacitor rectifying the signal, and
> there will pass a high current. So, you need large traces, ok? But the PWM
> controler needs a feedbak in the same net, and these trace can be very
> small... because no current flow through the PWM IC. But if you assume
that
> all the net must be drawn with the same routing style, you cannot make a
> small trace to the feedback...
>
>
> Em Qua 27 Out 2004 13:11, Bert Douglas escreveu:
> > Hello all,
> >
> > Is there any way to encode information about trace routing styles as an
> > attribute in gschem, so that this is passed on to PCB in the netlist?
> >
> > If not, then I can adopt a convention and encode this information in the
> > netname.  Then a small script can add the "style" notation so that PCB
> > can use it.  This leads to another question.
> >
> > Is there any way to split a net in gschem, so that instead of one big
> > net, there are two smaller nets?  For example, assume there is a net
> > like this:
> >        netname1  part1-pin1 part2-pin2 part3-pin3
> > then I would like to get this instead:
> >        netname1a  part1-pin1 part2-pin2
> >        netname1b  part2-pin2 part3-pin3
> >
> > I am doing this from memory and am too lazy right now to check the
> > syntax for netlists. So I probably got some details wrong. I hope this
> > is good enough to communicate the general idea.
> >
> >
> > Thanks,
> > Bert Douglas