CircuitSim is an interactive, real-time electronic circuit simulator written in Java using Swing.
It provides a visual sandbox-style environment where users can design circuits on a grid, connect components with wires, and observe live simulation of analog voltages, currents, and digital logic behaviour.
The application is designed for both learning and experimentation, offering continuous simulation updates as circuits are modified, along with support for custom components and reusable designs.
This is free and open source software.
Key Features
- Analog simulation: continuous DC-style solver for voltages/currents with short-circuit detection.
- Digital logic simulation: built-in logic gates (NAND/AND/OR/XOR/NOT) driving wires as 0V/5V signals.
- Custom components: dedicated editor with input/output ports, nesting, and local + temporary libraries.
- Editor UX: grid-snapped placement, multi-select, rotate, resize, pan, zoom, context menus.
- Component + wire palettes: grouped components, drag-and-drop placement, selectable wire colors.
- Properties panel: edit component parameters and titles in real time.
- Persistence: save/load JSON boards, autosave, undo/redo, temp custom-component mode.
- Cross-platform support – runs under Linux, macOS, and Windows.
Website: github.com/BlazingHotCode/CircuitSim
Support:
Developer: Nadav Babad
License: Apache License 2.0
CircuitSim is written in Java. Learn Java with our recommended free books and free tutorials.
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