On Mon, 3 Dec 2001 09:06:03 +1000, Matthew van de Werken wrote:

>I'm the exact opposite of this. I try to make each schematic part look like
>its function, rather than its physical layout. That way, the schematic will
>be a proper abstraction of the circuit, rather than a rough draft of the
>PCB. IMO it makes the schematic easier to read and understand if it's
>abstracted from the physical layout of the board.

And so would I but then I'm an electronics design engineer who does his own
PCB layouts not a PCB designer who considers the schematic to be some kind
of graphical netlist entry system. 

For the same reason I will be keeping power pins hidden in most situations.

For the original poster just unhiding the power pins will result is a mess
with overlapping annotations for most existing library parts. You will
likely have to revise the symbols to show power pins clearly. 

Taking your 74VHC00 example if you do show power pins are you going to show
them on all 4 gates like pin 7 and 14 will appear 4 times for each package?
Or do you show them on the first gate so the reader seeing the 3rd gate
will have to search the schematic for the 1st gate of that package to see
what supply it is running from? IMO both ideas are horrid. 

The suggestion of a '5th' part in the package just showing power pins is
okish but for a reader it is worse than just adding a power table to the
last sheet listing all packages and power pin connections. 

I have not yet had to do a thoroughly mixed 5/3.3v system with Protel but
if I did I would likely create symbols with hidden VCC3 and VCC5 pins and
annotate the symbols with 3v or 5v to give the 'reader' more information
where he needs it.

Cheers, Terry.

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