[SI-LIST] Re: [SI-LIST]: Which tool is the best - LINPARdiscussion

  • From: "Michael E. Vrbanac" <vrbanacm@xxxxxxxxxx>
  • To: raj.raghuram@xxxxxxxxxxxxxxx,
  • Date: Tue, 20 Apr 2004 13:44:20 -0500


I am not particularly well-versed in the intricacies of some of these numerical
methods and I do appreciate your explanation.  Such academic insight is
extremely helpful in developing the tools and explaining their processes and
how they might be better used.

There are a few questions I'd like to ask.  Since there's always pros and 
cons with
just about everything, and very seldom is extreme accuracy warranted, I would
be interested in just how much these details might make a very real difference
in the outcome on any real design decision based on the data received from
them.  How might these differences affect my design decisions and what sort
of errors might I need to deal with and would any other factors swamp out those
differences when applied in an everyday design decision?

For instance, I have used ApSimRLGC and got some phenomenally good results
from it on some pretty critical designs even multi-gigabit stuff.  The TDR
measurements were almost dead on and the cross-sections confirmed the
structural definitions.  I am hearing that in actual practice Linpar can do 
this as
well. So where would this stuff break down and under what conditions and what
would we expect to see when it does?  This sort of information is what I was
addressing earlier.  Its ok to use a tool within its capabilities but when 
you don't
know where that is (a lot of folks don't and are vulnerable), then there's 
likely to be
trouble.  A $100K tool used incorrectly can be easily be beat by one costing
$1K that is used within its capabilities.

I think most of us would agree that up to some point these things really do 
but after that, the differences are insignificant or the end-results would 
not be substantially
different any way you go. This gets to be important if the tool costs go 
from 1%
accuracy at a few thousand dollars to 0.5% accuracy at $50K.  Unless there
is some warrant for that additional accuracy, the extra half percent is not 
to be money well spent.  What would you advise us that would keep us out of the
"more dollars must be better" trap?  Where is the "best bang for the buck"?

Best Regards,

Michael E. Vrbanac

To unsubscribe from si-list:
si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field

or to administer your membership from a web page, go to:

For help:
si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field

List FAQ wiki page is located at:

List technical documents are available at:

List archives are viewable at:     
or at our remote archives:
Old (prior to June 6, 2001) list archives are viewable at:

Other related posts: