Re: Logic device (U) and switch level simulation

On Friday 12 September 2003 04:36 pm, Willis Shih wrote:
> There is a U: logic device in gnucap for logic mode
> simulation. How to run logic mode simulation on switch level
> devices like transmission gate logic? U device seems not
> suitable for switch level devices.

You could use a switch (S device).

The down side of this is that it doesn't have the "implicit 
mixed mode" automatic mode switching.  You may not need this.

The gnucap S device is more efficient than the spice equivalent.

What is really needed is a switch level "level" for the mosfet, 
and to enable the mode switching there.  Doing this also opens 
up an interesting new homotopy method, for improving 
convergence.

> BTW, is there any preprocessor to parse hspice netlists and
> models?

I keep hoping someone will make a configurable preprocessor to 
handle the many variants of spice formats.  Gnucap will take 
some HSpice extensions directly.