( ESNUG 382 Item 6 ) -------------------------------------------- [11/15/01]
Subject: Nassda, EPIC, Lawsuits, Avanti Hspice, Mentor Mach TA, Celestry
> Thank God, for the near-SPICE guys. If you're willing to be 1% to 5% off
> from a true SPICE sim, the near-SPICE guys will give you a 100X speed-up.
> EPIC pretty much owned this niche throughout the 90s. They were the "hot
> technology find" of DAC'94. Synopsys aquired EPIC in 1997 for $440
> million. Most of the original EPIC team left Synopsys within 2 years.
>
> Now there's a new near-SPICE company, Nassda, that's trying to steal this
> niche from Synopsys EPIC. "The Epic tools are getting pretty old when run
> against new designs," wrote John Szetela of AMD. "Nassda looks very good
> if you just want a super SPICE."
>
> - from "Back To The Future" column
From: Peter Denyer <peter.denyer@sun.com>
And now, John, we have Synopsys trying to stamp out Nassda as a competitor
by saying these ex-Synopsys folks misappropriated Synopsys IP. It's
getting to the point where an EDA developer can't take on a new job without
threats of lawsuits. What's this EDA industry coming to?
- Peter Denyer
Sun Microsystems
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From: "John Lee" <jolly@avanticorp.com>
Hi John,
Good article; I enjoyed it! But you forgot to mention Avanti Star-Hspice
was the biggest player in this market. The Dataquest numbers give us 78%
market share.
Also the new "fast-SPICE" simulators (like Star-Sim and Nassda) rely upon
hierarchical techniques to get speed. The key issue is not how to solve a
large number of transistors quickly, but how to handle post-layout
parasitics that are:
a. Flat in nature, hence destroy the notion of hierarchy.
b. Necessary for any timing, power, IR, EM or noise analysis.
c. Overwhelm simulators in volume of parasitics.
d. Confound users, because the flows are so difficult to set-up. Ask
people how much time they can spend setting up a post-layout
back-annotation flow into schematic netlists.
So the issue is not how to simulate transistors --- we've known how to do
this for a while --- but how to simulate transistors with flat layout, while
preserving the benefits of hierarchical simulation. Star-Sim plus Star-RC
is our solution to this problem. We've been hierarchical for 2 generations
now, and we've focused on is how Star-Sim handles parasitics faster.
- John Lee
Avanti Fremont, CA
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From: "Daniel Payne" <daniel_payne@mentorg.com>
Hi, John,
I agree with your observations on the Spice world.
Mentor also has a big, fast Spice tool, called Mach TA. Our customers have
seen it perform 4X faster than Hsim on PLLs and any design that has
extracted RC interconnect.
- Dan Payne
Mentor Graphics
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From: "Ed Hepler" <elh@ece.villanova.edu>
John,
You may have forgotten about Lsim from SCS (later acquired by Mentor). It
had Adept mode switch level simulation back in the mid-late 80s that was very
good. Since Lsim was "mixed-mode", part of your circuit could be at the
transistor switch level, other parts could be at the transistor adept level,
while other parts could be described using their behavioral language (M). M
allowed one to do things that are still not possible with VHDL or Verilog.
Later a VHDL front end also became available. Since M was really a superset
of C, you could say that it was the first C based simulation language. :-)
If you wanted "real" SPICE accuracy, you could tell Lsim to send that part of
your circuit to HSPICE (either running on the same host machine or some other
one on the network.) All the results were reported back in the same waveform
displays through Lsim.
Many of the SCS tools were way ahead of their time. Unfortunately, I don't
think Mentor knew what they had purchased and many of them "disappeared" in
favor of "Falcon based" tools that didn't have all of the nice features.
- Ed Hepler
Villanova University
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From: Tom Arns <tarns@SandCraft.com>
Hi John,
Mentor is also a player in the near-SPICE market with Mach-TA. We have a few
copies here, and are able to simulate fairly large datapaths with it. It's a
step up from ADM, which is now owned by Avanti, and called Star-SIM. Avanti
had not been keeping ADM up-to-date, and lost a lot of the business to Nassda
and Mach-TA. They have recently come out with a version of which is intended
to compete with Nassda, but I haven't benchmarked it.
We have benchmarted Nassda, but didn't see enough advantages over Mach-TA to
get any licenses. Nassda's fairly expensive.
With these new high speed SPICE simulators, the limiting factor is often
extraction, rather than simulation capacity. Who cares if you can simulate
your cache in a few hours if it takes 3 weeks to run a detailed enough
extraction?
- Tom Arns
SandCraft
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From: [ Vault 713 ]
Hi John,
Interesting timing of your Gadfly "near-Spice" article. We are looking at
Celestry's UltraSim and there was no mention about them. We're planning to
evaluate the tool in the near future. Unfortunately, our evaluations are
often far too brief and only tell us part of the story. If we get any
meaningful data, I'll let you know.
I checked your DAC '01 write up and found no quotes from actual users of
Celestry. The only quotes were from people who have seen their demos and
presentations. Is there any chance of soliciting data from actual Celestry
users in you next ESNUG mailing? Celestry was willing to give us user
references, but I prefer ESNUG information than that of handpicked
vendor references.
As usual, if you quote me, please keep my name anonymous.
- [ Vault 713 ]
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