Dynamic Control Of Time-domain Analysis In The Spice-pac Simulation Package

SPICE-PAC is a circuit simulation package which is upward compatible with the popular SPICE-2G6 simulation program. Although SPICE-PAC constitutes the "core" of several interactive simulators, the best use of its flexibility is in "integrated" software tools in which circuit simulation is combined with other software tools for circuit optimization, device parameter fitting, multi-level simulations, etc. Recently the package has been subjected to a series of modifications required by "enhanced cir cuit simulation", i.e., computer-aided circuit analysis that allows users to extend, modify and replace some of the "standard" sim- ulation capabilities. This paper describes modifications which provide "external" run-time control of time-domain (transient) analysis, and shows simple applications of this mechanism.