Digital - A simulator for digital circuits.
LTspice - LTspice® is a high performance SPICE simulation software, schematic capture and waveform viewer with enhancements and models for easing the simulation of analog circuits.
BOOLR - Open-source digital logic simulator
Wired Logic - Wired Logic is a pixel based logic simulator.
Logicly - - Design circuits quickly and easily with a modern and intuitive user interface with drag-and-drop...
Fritzing - Fritzing is an open-source initiative to support designers, artists, researchers and hobbyists to...