EEcircuit is a circuit simulator based on ngspice, and it runs inside the browser using WebAssembly technology. The input is schematic, and the output is the results of the analysis that you're doing in the simulations. You are able to plot and view the results directly in the browser using a high-performance WebGL plotting library webgl-plot, or download the data in CSV format for further analysis. Notice that your schematic and results are processed locally and always remain inside your browser and are never uploaded to the network. The focus of this implementation is rapid analysis and sharing circuit ideas and results within the VLSI and chip-design communities.
The next version of EEcircuit has been released! If you still require the old version go to gen1.EEcircuit.com.
For a user guide, go to help.EEcircuit.com.
Watch the launch presentation video 📺
The repository expects the sibling ../EEcircuit-schematic package because it is a local file dependency. Install with npm ci, run npm run check, and run npm test for the sequential headed local-Chrome suite. Video-generation tests are separate and are not included in npm test.
Deployment uses Wrangler and the Cloudflare configuration in wrangler.jsonc.
The application reads and writes EEcircuitV2 documents. V2 schematic connections are explicit: a connected wire endpoint has a terminal or junction reference, while an endpoint without a reference is electrically floating even if it shares a terminal's coordinates. Canonical saves may store a net name on one representative wire instead of repeating it on every connected segment.
EEcircuitV1 is obsolete and cannot be opened directly. When a V1 file is selected, the application offers to convert and download a separate V2 file. The converter rejects ambiguous or invalid wiring rather than changing the circuit by guessing.
To learn more about SPICE netlists, refer to the ngspice manual.
EEcircuit is built on top of Ngspice, Emscripten, React, Vite, and Cloudflare Wrangler.