Reply-To: "Kevin Aylward"
From: "Kevin Aylward"
Subject: Re: Working Spice for Linux?
X-Newsreader: Microsoft Outlook Express 6.00.2800.1106
Date: Fri, 18 Oct 2002 22:05:42 +0100
NNTP-Posting-Date: Fri, 18 Oct 2002 22:05:43 BST
"Charles DH Williams" wrote in message
> In article , Spam Hater
> > It's not a matter of their programming skills. It's their not
> > understanding the underlaying mathematics involved.
> > There's some -serious- math going on inside there. All of the
> > versions I've seen, and I've looked at a few, were done by people
> > without the necessary knowledge of the mathematics involved.
> Which versions have you looked at, and what were the problems?
> It is possible to make very useful improvements to Berkeley's spice3
> without ever touching the mathematical parts of the programme. In any
> case, the mathematics used in Spice3 is not beyond anyone with a bit
> motivation and the math background you'd get in, for example, a
> engineering degree.
For instance, the basic BSim3 code in Spice3/Spice does not have
externally available terminal currents, i.e. id, is, ig, ib. This is a
real pain as you want to probe pins post simulation, without putting in
I fixed this in my XSpice port (for dc and transient anyway) by
guesswork. I looked at the code and data structures in the mos1,2,3
models, and guessed what the equivalent names were in the bsim ones.
Note there is no documentation saying what is what. I set up a test
circuit with resisters in the nodes to probe the currents and used trial
and error on the code until the pin currents matched. I also used
pattern recognition to add the relevant support for the .save @m1(id)
Even getting the basic code to compile under windows only took a few
hours, and I'm an analogue engineer, software, as I have mentioned many
times, is only a hobby of mine.
SuperSpice, a very affordable Mixed-Mode
Windows Simulator with Schematic Capture,
Waveform Display, FFT's and Filter Design.