The first generation of NL (non-linear) analog simulator was developed in the late 1980s for different types of computers and operating systems.

For many years it was a proprietary tool of a few research labs and small companies, used to design control systems, measurement equipment, and power supplies.

For mixed-signal systems, system-level, and behavioral modeling NL5 uses simple basic digital, function, C-code, and DLL components.

A special algorithm is in place to handle simulation with ideal components (e.g. zero/infinite resistance and instantaneous switching).

NL5 performs 3 types of AC analysis: Without a license, NL5 works in a demo mode, with full functionality and limited number of circuit components.