[TUHS] Unix Circuit Design System

Jeremy C. Reed reed at reedmedia.net
Fri Jan 1 09:58:41 AEST 2016

On Thu, 31 Dec 2015, Larry McVoy wrote:

> Any chance this was code that turned into the Ousterhout stuff, I think it
> was called spice?

While I am not involved with it at all, I did interview a couple 
developers toward my BSD history book. (The following is from my 3BSD 
"Welcome to Virtual Vax/UNIX" chapter.)

\textsc{Spice} 2\index{SPICE}, the Simulation Program with Integrated 
Circuit Emphasis, was another program that benefited from the VAX work. 
This Fortran program predicted the electrical characteristics of an 
integrated circuit.  Spearheaded by professor Donald O. 
Pederson\index{Pederson, Donald O.}, who helped establish a fabrication 
lab --- the first integrated circuit fabrication facility at any 
university\cite{donpederson2005} --- in the 1960's, it was developed by 
the integrated circuits group of the Electronics Research Laboratory and 
the Electrical Engineering department [at University of California at 
Berkeley] in the mid 1970's.

To many it is considered the first significant open source program.
The program was available free of charge, for
not-for-profit uses to any interested party.
% above CITE archives/1970s/3bsd/usr/src/cmd/spice/roots.f
Its source code was distributed for the cost of writing the 
tape and copying the documentation, so it was decided to 
include it on the BSD distribution tape as well.\cite{tom-quarles-1}

\textsc{Spice} was originally developed to run as a batch program in 
punched-card form on the university's CDC 6400 system outputting to a 
132-column line printer, but its default allocation of 400,000 double 
precision numbers in an array wouldn't work with the PDP-11.  It was 
later ported to many operating systems and machines that had adequate 
memory and floating point capabilities, such as VMS and Unix on the 

The program shipped with BSD provided general-purpose circuit
simulation for nonlinear DC, nonlinear transient, and linear AC
analyses.  Circuits could contain resistors, capacitors, inductors,
mutual inductors, independent voltage and current sources, four
types of dependent sources, transmission lines, and the four most
common semiconductor devices: diodes, bjts, jfets, and
% ALSO same in archives/1970s/3bsd/usr/man/man1/spice.1

Virtually every electronic chip --- even today --- used \textsc{Spice} 
or one of its derivatives at critical stages during its
design.\cite{donpederson2005} In fact, its name has become
a verb in the industry: ``let's \textsc{Spice} that circuit
and see if it works!''

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