RE : [SI-LIST] : Need your comments in selection of SI simula

Weber Chuang (WeberChuang@via.com.tw)
Mon, 20 Apr 1998 15:03:03 +0800

Dear Allen,

We are also currently using QUAD/xtk, and Hspice as well, like what
Michael said, QUAD is mainly a post-layout analysis tool, you can't
combine it with your router automatically to do routing based on
electrical rule or class(at least I do not know how to, and I heard from
one of my friends that Cadence can do this, Mentor has a toolkit called
Board-500 that can do this, but the calculating engine seems to be
QUAD/xtk/xfx which is now merged by Viewlogic/Synopsys). But the
accuracy is good if you can build correct environment(module, stackup,
IBIS, connector...). We will have more correlation work done once we get
the TDR and 10GHz scope next month.
To do SI analysis, you need to be pretty familiar with the S/W's
platform as well as transmission line theory and PC system architect(I
know you are PC system maker), only then can you fully understand what
you are doing and how to improve the SI issue as well as simulation
accuracy. There might be a long way to go.
For SSO noise, there is little that a system house can do, but you can
focus on signal integrity as well as static timing analysis(QUAD has a
tool called MOTIVE that can accept the output of XTK, in the new release
of Mentor's S/W, they have something alike(called TAU or what), I don't
know the status of Cadence, you may need to check it out, we develop our
own in-house tool for this purpose with PERL and VBasic/excel).
By the way, good supporting is also a very important factor, as far as
I know, the supporting FAE of QUAD/xtk in Taiwan has just joined Mentor
Taiwan in April, he knows QUAD/xtk somewhat, but it might take 2 or 3
months for him to get used to Mentor, Viewlogic/QUAD might need the same
time to build up a new supporter though maybe not mature enough,
supporting people of Cadence is from PCB side(but really senior, he was
my colleague while I was in Mentor), not from RD side(maybe they have
hired new staff now, you need to find out). I try not to stand in favor
of any side, and I hope it helps.

Best Regards

Weber Chuang(ChingFu Chuang)
SI Group Leader, System Team.
VIA Technologies, Inc.
Taipei, Taiwan, ROC
http://www.via.com.tw
Very Innovative Architecture

> -----Original Message-----
> From: Michael Cohen [SMTP:micohen@us.ibm.com]
> Sent: Thursday, April 16, 1998 10:52 PM
> To: si-list@silab.Eng.Sun.COM
> Subject: Re: [SI-LIST] : Need your comments in selection of SI
> simula
>
> >> Dear sir:
> >>
> >> Currently, we are preparing to introduce the signal integrity
> CAD tool
> >> into our motherboard design flow. The two candidates are Quad
> and
> >> Mentor. Can you kindly give us your opinions about the product
> of
> >> those two company such that we can make a proper selection.
> >>
> >> Best regards!
> >>
> >> Allen
>
>
> We currently use the Quad XTK toolset, but are seriously looking at
> using the
> Cadence SPECCTRAQuest toolset, as Quad XTK does not give us an
> adequate early,
> pre-route, SI solution. We will continue to use Quad XTK for
> post-route
> analysis.
>
> The key to any decision you make is what do you already have in place
> for the
> rest of you CAD tools (schematic capture, board placement, board
> routing,
> etc.). If the majority of your tools are Cadence, then you should
> seriously
> investigate SPECCTRAQuest. If they are Mentor tools, stay in that
> line. If
> the tools are a hodgepodge of vendors, you should look into bringing
> them into
> one, either Cadence, Synopsys (Quad & ViewLogic are now owned by
> Synopsys), or
> Mentor. All these tools have their strenghts and weaknesses; the
> other key is
> to determine your company's needs and work from them. Don't make a
> rash
> judgement; bring them in, evaluate them, then make YOUR decision.
>
> Mike