VISIO

[Christopher_List at Sonymusic.Com]

Mr Pulver wrote:
> Visio started life as a glorified presentation tool for marketeers.
> It's grown up into a WONDERFUL piece of software for flow-charting,
> computer network diagrams, and yes, even schematic drawings.
>
> *BUT* Visio is NOT an emulator like say Electronics Workbench is.
> Also, it will NOT product circuit layouts for boards.
> It's "meerly" a graphics tool that ha sa lot of built-in icons that help
you do diagraming.

Well.... it can do circuit boards - sort of.

The nice thing about Visio is that it's got these things called "stencils"
and each stencil can have user-defined "connection-points" and lines will
"glue" to these connection points and stay connected where ever you move
the stencil. I've created a little library of stencils for ICs, resistors,
trimmers, etc, at 1:2 scale (i.e. 2/10" pin spacing) with little diagrams
drawn on them showing stuff like the +/- and output pins for op-amps,
various gates, etc. and with connection points at each of the pins. I use
them to do to-scale layouts of circuits before building them on protoboard
so as to minimize the number of jumpers I'll need and the amount of board
space required. It's nice because once I get all the connections right, I
can move around the ICs, resistors, etc. and the lines connecting the pins
stay connected - so I don't have to worry about the schem anymore.

It takes some work to figure out how to make your own stencils with
connection points defined and what not, but once you get a stencil for each
package size, you just duplicate it and change the drawing on it for a new
chip....

Anyway, once upon a time I thought about actually etching a board or two
and so I tried making stencils of pad layouts at 1:1 scale - as little
squares with little holes in the middle based on my 1:2 IC stencils - it
worked great. The big problem came when routing the traces. If you have
straight lines, everything is fine, but once you take a single line and add
bends and right angles to it - at spots you choose - Visio will stop
enforcing the "connection" because it doesn't know how you want the line to
be routed when one of the stencils is moved. - This can get rather
frustrating. It also doesn't allow for a high degree of accuracy in
specifying your line widths.

Anyway, if anyone is playing with this for doing layouts and would like a
copy of my stencil file, let me know...

- CList