Skip long startup runs.
Solve the repeating steady state directly, so you can measure stable ripple without waiting for startup behavior to settle.
Power electronics simulation
Design and test switching converters in your browser.
PWMSim helps you edit a circuit, run a simulation, inspect waveforms, take measurements, and compare design options.
No installation or account needed. Simulations run on your computer.
Free, no accountNo run limits, circuit-size limits, or timed
sessions.
Circuits stay putYour circuit stays in your browser and is
never uploaded.
Portable workSave projects locally and export netlists,
schematic images, and reports.
Tools made for converter design
Reach a useful result faster, then check the supporting files on the validation page.
Measure the result.
View voltage and current, add calculations, use cursors, save measurements, and inspect the frequency spectrum for a selected time range.
Compare design points.
Test a list of component values. Every test point shows its result or error, so failed points never disappear from the comparison.
Check the validation evidence
Each benchmark includes the netlist, measurement steps, and allowed tolerance. Open the same file in LTspice and verify the result yourself.
18/18
examples with a numerical result or a clearly stated export limit
8/8
exportable examples that pass their LTspice checks
38/38
same-file LTspice comparisons that pass
0
cookies, accounts, or circuit data sent in usage reports
What it does not do yet
PWMSim tells you when something is unsupported. It does not silently guess.
- ImportSome LTspice behavioral models and subcircuits are not supported. The import report shows what worked, changed, or failed.
- MotorsThe motor-drive interface is experimental and is not a supported feature.
- PFCLine-cycle PFC controllers are not supported.
- ConvergenceWe do not claim that PWMSim solves circuits that other simulators cannot.
Try a buck converter in about two minutes
Open the example, change the switch duty, run it again, and measure output ripple with two cursors. Save or export the project when you finish.
Need batch runs or automated
checks? These features are not available yet.
Tell us what you need.