Overview of PSpice

History

PSpice is a circuit simulation tool owned by Cadence Design Systems, and stands for PC Simulation Program with Integrated Circuit Emphasis.  Originally developed in the 1980/s by MicroSim, it was one of the first commercial electronic simulation tools developed for the IBM PC platform.  Almost from the beginning, due to the easy availability of a demo version, , PSpice was in standard usage in electrical engineering departments throughout the United States.  However, since it was such a common program, there were many basic assumptions and conventions that were not well documented, since once you had learned these basics they seemed obvious.  It is to cover some of these basics that these pages are designed.

What tools make up PSpice?

One of the first questions that comes up when working with PSpice is “What program do you run to ‘do’ PSpice?  This comes up because PSpice is actually what is know as a ‘back-end’ program.  It is usually not run directly, but instead is run from some other program.  PSpice uses netlists and model files to do the simulation, but these can be pretty difficult to create by hand, so most users use some type of ‘front-end’ tool to create their designs.

The most common front end used today is Capture and Capture CIS, created originally by OrCAD, but now owned by Cadence.  In Enterprise tool packages sold by Cadence, Capture CIS is referred to as Allegro Design Entry CIS (usually abbreviated DE CIS.)  On these pages, we will generally just refer to them as Capture.In the early ‘90s OrCAD and MicroSim merged, and the first result of that merger was to tie Capture, then the most popular PC based schematic entry tool, and PSpice, the most popular simulation tools together.  While early versions of this combination left a great deal to be desired, after version 9.2 Capture became a usable front end for PSpice, and after versions 15.0, became fully as useful as the earlier Schematics program. 

PSpice Schematics was the original schematic capture tool created by MicroSim, and is still preferred by many users today.  It was designed strictly to be a front end for a simulation tool, and so has many common tasks streamlined for ease of use that the more generic Capture makes more difficult.  While OrCAD and then Cadence have been trying to end production of Schematics for many years, the loyal (fanatical!) user base has required them to continue to produce a version of Schematics for each new release, even though no new features have been added for years.  If you are using Schematics as your front end for PSpice, you will find that you need few of the hints needed in these pages.  They won’t come up!