Spectrum Software was a software company based in California, whose main focus is electrical simulation and analysis tools, most notably the circuit simulator Micro-Cap. It was founded in February 1980 by Andy Thompson. Initially, the company concentrated on providing software for Apple II systems. One of the earliest products was Logic Designer and Simulator. Released in June 1980, this product was the first integrated circuit editor and logic simulation system available for personal computers. In many ways it was the forerunner of the Micro-Cap products. Its primary goal was to provide a “circuit creation and simulation” environment for digital simulation. In August 1981, the analog equivalent of the first program, Circuit Designer and Simulator, was released. Its integrated text editor created circuit descriptions for a simple, linear, analog simulator. September 1982 saw the release of the first Micro-Cap package as a successor to the Circuit Designer and Simulator. The name Micro-Cap was derived from the term Microcomputer Circuit Analysis Program. As of July 4, 2019, the company has closed and the software is now free. References Micro-CAP: An Analog Circuit Design System for Personal Computers Spice Programs: Computerized Circuit Analysis For Analog EEs Analysis of digital filters via SPICE-family programs Modeling IIj Noise in HEMTS with SPICE-Based Micro-Cap AC Analysis of Idealized Switched-Capacitor Circuits in Spice-Compatible Programs White Paper: A New Zobel Network for Audio Get more power with a boosted triode External links Spectrum Software Homepage About Spectrum Software Micro-Cap Application Notes Software companies based in California Companies based in Sunnyvale, California Defunct software companies of the United States