CircuitLogix simulates analog, digital, and mixed analog-digital circuits. The simulator first divides the circuit into analog and digital portions. The analog circuitry is simulated with the time-step driven SPICE engine, while the digital parts are simulated separately with an event-driven simulation engine. The CircuitLogix digital engine was developed directly in .NET, faster than SPICE macros. Because the simulator automatically performs signal conversion, it is possible to connect any analog or digital part to any other. The system’s model library contains hybrid parts for analog-to-digital and digital-to-analog conversion.