Re: [SI-LIST] : skin effect and transmission line simulators

Jonathan Smith (
Fri, 5 Sep 1997 11:28:50 -0700 (MST)

Hi Chris:

The Pacific Numerix toolsuite can handle all five of the requirements that
you specified.

On Thu, 4 Sep 1997, Chris Simon wrote:

> I am looking for a time domain lossy transmission line simulator for
> digital signals with bit rates of 1Gbit/sec and higher. I would like to
> get information on simulators that you have experince with.
> The simulator I'm looking for should include all of the following:
> 1. The results can be viewed in the time domain.
> 2. Transmission line models that include series resistance and
> inductance which are functions of frequency to ACCURATELY model skin
> effect. (i.e., a frequency dependent line model that is used to get time
> domain simulation results)

The SPICE simulator from Pacific Numerix does accurately model
lossy dispersive lines including the frequency dependent resistance and
dielectric conductance for dielectric loss.
All frequency-dependent parasitics (RLGC) are produced
automatically from any layout tool database, in 2-D or 3-D.

> 3. SPICE CMOS models and/or IBIS type non-linear models can be used
> as drivers and receivers

Of course, Pacific Numerix provides a tool that converts the data
from IBIS information sheets into Pacific Numerix SPICE models, and these
can be used in the SPICE simulation. Where a higher level of accuracy is
needed, the Pacific Numerix tool can automatically generate and run the
SPICE of your choice, for instance whatever SPICE version you may have
transistor-level driver/receivers from.

Jonathan Smith
Consulting Engineer

> 4. Arbitrary driver data patterns can be used (i.e., not limited to
> repetative signals)
> There is one other criteria, but I'm not certain that this one is required
> for signals with 150 to 200 pSec rise and fall times. Any opinions?
> 5. Includes the effect of dielectric losses.
> I am aware of several products that claim to meet these critria. Upon
> close inspection several of the lossy line models didn't really meet number
> 2. This seems to be the tough one.
> I am going to take a detailed look at Microwave Design System (MDS) from
> Hewlett-Packard, although someone told me that the current version doesn't
> meet number 3 above.
> I would be interested in hearing which of the above criteria are met by
> other tools, or whether a future revision will incorporate these features.
> If you know how the following tools stack up, especially with regard to
> number 2, I would appreciate hearing from you.
> Quad Design, Quantic, Interconnectix/Mentor Graphics, Pacific Numerix,
> Cadence SigNoise, ApSim/Contec, EMC-workbench, others?
> Chris Simon