Multisim

Multisim is industry standard SPICE simulation and circuit design software for analog, digital, and power electronics in education and research.
Multisim integrates industry standard SPICE simulation with an interactive schematic environment to instantly visualize and analyze electronic circuit behavior. Multisim has an intuitive interface that helps educators reinforce circuit theory and improve retention of theory throughout engineering curriculum. Researchers and designers use Multisim to reduce PCB prototype iterations and save development costs by adding powerful circuit simulation and analyses to the design flow.