Jennifer Jenkins wrote:
> I am looking for information on any CAD packages (software) used for or
> specific to flexible circuit design.  I would appreciate any help.

Hello!
 I was just going through some old mail, and realized that you never 
really received a good answer to your question (not in public, anyway)

I have limited experience with flex. I have only done a few designs 
but I have a LOT of reference material...
As far as I know, there are NO CAD packages specific to flexible 
circuit design, because there really isn't too much difference between 
rigid and flex from a computer point of view. Gerber data is Gerber 
data. 

The fabrication drawing is virtually the same, except that you will be 
using appropriate notes to call out different materials, and different 
specs or standards to be used for acceptability. If components will be 
mounted to the flex you may need to consider stiffeners and adhesive 
to provide stability, which will also have to be noted on the fab dwg.

You may need the help of a mechanical package to calculate dimensions 
if bend radius or folding is required (most PCB layout tools aren't 
too hip with that third dimension).

But as far as the actual layout is concerned, the same rigid-board 
layout tools will work just fine as long as you understand the rules. 
Rules like "keep the trace routing perpendicular to the bend", "no 
vias in a continuous flex area", "stagger traces on multiple layers to 
reduce I-beam effect", stuff like that. You didn't really give much 
info in your message, so its hard to know what you were looking for. 
Most flex vendors have guidelines that they will cheerfully give to 
you (makes their life easier if you follow them), there are several 
excellent books on the subject (I used Ken Gilleo's "Handbook of 
Flexible Circuits", but I know Joe Felstad has a new one out, too), 
and the IPC has a few publications that might help.
 
Flex / rigid-flex can be challenging, but I enjoy it a lot. Good Luck! 
 
								Jack