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Re: gEDA-user: preferred power connection style?



I'm leaning towards putting the power pins either on the device itself, if there aren't to many power pins, or in another block if there are. It used to be simply a single power rail and we all called it VCC for digital +5V but nowadays in some of the devices I use there are 3 different power rails. The net approach is cleaner if all the symbols you use are yours but if you import any then you have a problem as the style and net naming may be different for a lot of the power signals. This may cause more problems than it's worth.

My personal vote is to define them as pins either in the same block or as a separate block.

Mark



Jan Stap wrote:
Hi Richard,

On Sun, Feb 16, 2003 at 06:51:26AM +1300, Richard Barrington wrote:

Hi,

I'm a new gEDA user, and have just made an additional micro-controller
component as per the docs, but the components on-line mostly see to
provide power pins rather than using power nets. Explicitly defining
them as pins makes more sense to me, particularly when you have multiple
power inputs (Vss, Vssa), but the docs suggest doing it the other way.
So it prompts me ask which is correct / preferred?

Richard.

I'm new to gEDA too and a wondering about the same thing (did not post
the question yet though). The doc on this topic (net= attribute mini-HOWTO,
http://www.geda.seul.org/docs/20021103/netattrib/netattrib.txt) advises
to use net= attributes for the power pins, without visible power pins on
the symbols. It also signals the fact that most symbols in the current
library await addition of the net= attribute (and I guess removal of the
visible power pins).

But I wonder how to go about this for e.g. a DC-DC converter that I am planning to use, which is providing power for the rest of the circuit. And how to go about auto-power-down circuitry, where one part of the circuit is shutting down or re-powering another part. This requires
defining net= attributes for each part of the circuit that shares its power supply. With regard to readability of a circuit, I guess it's a trade-off between having to match net= signal names, or having possibly many power wires running around.

Experienced gEDA users out there: please comment.

Thanks,

Jan Stap