Circuit Tree Alternatives

Sketch, simulate, and share your circuits, entirely in your browser -- no install required.

Logisim is an educational tool for designing and simulating digital logic circuits.

Wired Logic is a pixel based logic simulator.

System Verilog, Verilog, VHDL, SystemC HDL Simulator for ASIC Design and Verification

Open-source digital logic simulator

For engineers who want to expand the possibilities of power electronics.

A simulator for digital circuits.

Animated electronic circuit simulator using ideal components to visualize voltage and current.

Qucs, briefly for Quite Universal Circuit Simulator, is an integrated circuit simulator which means you are able to setup a circuit with a graphical user interface (GUI) and simulate the large-signal, small-signal and noise behaviour of the circuit.

HDL Simulator of System Verilog, Verilog, and VHDL for ASIC design and verification.

LTspice® is a high performance SPICE simulation software, schematic capture and waveform viewer with enhancements and models for easing the simulation of analog circuits.

ModelSim-Altera Software

System Verilog, Verilog. VHDL, SystemC, HDL simulator targeting ASIC and large FPGA designs.