Simulating Different parts of design one at a time.

I'm working on a combination digital/analog project and the simulation
time for the entire design is several days. I was told by one of my
professors that it is possible to run two simulations to verify its
output.

The idea being, run the first part, and store its output to a file,
then run the second part with its input coming from the output file of
the first part.

If anyone has any experience with this, I would appreciate it.

Feel free to send email to javery@andrew.cmu.edu

Thanks,

Jarrett

 

[vdvalk@rogers.com]

Verify is an interesting word.

I assume that the "simulation time for the entire design" is an analog
simulation. This in itself is an approximation of what happens.

In the "digital" space, the behaviour of interest can be simplified
into what is known as a "digital" simulation. (i.e. 1's and 0's rather
than
analog voltage levels) This type of simulation is ordersof magnitude
faster that "analog".

Tools to partition the design into "analog" and "digital" are commonly
refere to as analog-mixed-signal or "AMS" tools.
The idea is that a mixed mode simulation should be orders of magnitide
faster than the straight analog simulation.

It is, (of course ;^), left as an exercise to the reader, to understand
the innaccuracies introduced at each step of abstraction, and to the
problems introduced at the analog to/from digital interface in the
mixed mode simulation environment.

-- Gerry