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Welcome to the Gnucap home page!

Gnucap is the Gnu Circuit Analysis Package.

The primary component is a general purpose circuit simulator. It performs nonlinear dc and transient analyses, fourier analysis, and ac analysis. It is fully interactive and command driven. It can also be run in batch mode or as a server. Spice compatible models for the MOSFET (level 1-7), BJT, and diode are included in this release.

Gnucap is not based on Spice, but some of the models have been derived from the Berkeley models.

Unlike Spice, the engine is designed to do true mixed-mode simulation. Most of the code is in place for future support of event driven analog simulation, and true multi-rate simulation.

If you are tired of Spice and want a second opinion, you want to play with the circuit and want a simulator that is interactive, you want to study the source code and want something easier to follow than Spice, or you are a researcher working on modeling and want automated model generation tools to make your job easier, try Gnucap.

New features in the current release (0.31)

  • BJT model.
  • "Binning" for all MOS models.
  • Internal element: non-quasi-static poly-capacitor. (needed by BJT).
  • Enhancements to the data structures and model compiler to support binning in general.
  • A line prefixed by "*>" is not ignored, in spite of the fact that "*" usually begins a comment. This is a deliberate incompatibility with Spice. If you prefix a line by "*>" it will be interpreted as a non-comment in Gnucap, but a comment in Spice.
  • Circuit line prefixes of ">" and command prefixes of "-->" are ignored. This is so you can copy and paste whole lines, without having to manually remove the prompt string.
  • News/Announcements

    March 26, 2002
    Version 0.31 released.

    Return to the GNU project home page.

    Please send FSF & GNU inquiries & questions to gnu@gnu.org. There are also other ways to contact the FSF.

    Please send comments on these web pages and Gnucap to bug-gnucap@gnu.org

    Copyright © 2001 Albert Davis aldavis@ieee.org

    Verbatim copying and distribution of this entire article is permitted in any medium, provided this notice is preserved.

    Updated: $Date: 2006/11/24 10:52:38 $ $Author: ramprasadb $