Micro-Cap

Micro-Cap is a SPICE compatible analog/digital circuit simulator with an integrated schematic editor that provides an interactive sketch and simulate environment for electronics engineers. It was developed by Spectrum Software and is currently at version 12.
In July 2019, Spectrum Software closed down and Micro-Cap was released as freeware, and they no longer provide technical support or software updates. Previously, Micro-Cap was only available under a paid commercial license.
Version history.
The name Micro-Cap was derived from the term Microcomputer Circuit Analysis Program. The forerunners to the Micro-Cap simulator were the Logic Designer and Simulator. Released in June 1980, this product was the first integrated circuit editor and logic simulation system available for personal computers. 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.