Why most "free" online circuit simulators break on simple circuits (and what actually works)

说明与用途

许多免费在线电路仿真器限制组件数量并产生难以理解的错误，导致即使是简单的电压分压器也无法仿真。作者分析了这些限制，解释了常见的求解器错误，并推荐了真正免费的工具：Falstad、EasyEDA、CircuitLab 和 CircuitForge。

问题

Free online circuit simulators often impose component limits or lack proper error diagnostics, preventing users from building even basic circuits like a loaded voltage divider.

结果

Users gain clarity on which free simulators truly support basic circuits, understand typical solver errors, and can select the right tool for their workflow.

工作流

• 1. Search for free online circuit simulators. 2. Review pricing pages and tier limits. 3. Test a loaded voltage divider (5 components). 4. Observe component caps or lack of saving. 5. Identify error messages (Singular Matrix, Convergence Failed). 6. Learn common causes: missing ground, floating nodes, zero-resistance loops. 7. Evaluate tools: Falstad (free, no caps), EasyEDA (free, ngspice), CircuitLab (paid, accurate), CircuitForge (free, 3D breadboard).
• 8. Choose tool based on project goals and budget. 9. Export designs if using tools with upcoming EOL (e.g., Multisim Live).

证据

A lot of popular options market themselves as free simulators, but their free tiers cap out before you can build a single real-world circuit.

来源

When a simulator throws a "Singular Matrix" or "Convergence Failed" error, it means the matrix cannot be inverted mathematically.

来源

If you rely on Multisim Live, NI has scheduled its End-of-Life for September 15, 2026.

来源