Re: gEDA-user: Embedded Power Pins

[Xtian Xultz <xultz@xxxxxxxxxxxx>]

Em Sex 03 Mar 2006 21:32, John Luciani escreveu:
> The gschem logic symbols seem to have embedded Vcc and GND connections
> (at least the ones that I was looking at). Since I am working on a
> board that has 3.3V and 5V logic this is a problem.
>
> I created a script that takes a logic symbol with embedded Vcc and GND
> nets and creates (1) a new symbol with the power nets removed and (2)
> a new symbol with two power pins. My plan is to place power symbols
> (and decoupling caps) for each IC in a separate section of my
> schematic.
>
> Since many symbols contain the same pinout for power pins the power
> pin symbol is a symlink to a generic symbol. The new symbol without
> power pins have a _np suffix. The symbol containing the power pins has
> a _pwr suffix.
>
I allways used that way. I redrawed all my symbols to fit that standard. 
Unfortunatelly, there are a lot of people that dislikes that way.
IMHO all the pins used in a component must be showed on the schematic, no 
matter what the pin is. I have a lot of boxes with power pins, and its a good 
way to place decoupling caps.
When you mix analogic components with digital, its common to have, for 
example, two 5V, one for the digitals and another for the analogic. If you 
use the embedded pins, they will all use only one power supply. And when 
routing the board, its better to know exactly where all the connections go 
taking a look at the schematic.