Simulation
Circuit simulators that run entirely in your browser — no install, no account. Use the circuit simulator to see how a circuit itself behaves, and the IBIS waveform simulator to check signal quality after a PCB trace.
CircuitJS1 circuit simulator
Wire up resistors, capacitors, inductors, diodes, transistors, op-amps and logic ICs on screen and watch current flow and waveforms in real time. Click any component to change its value and the waveform updates immediately.
- Over 300 example circuits, from Ohm’s law to switching supplies, PLLs and a CPU
- Animated current flow makes it useful for teaching and learning
- Built-in scopes for voltage, current, power and FFT
- Save and load circuits as text, or share them by URL
CircuitJS1 was written by Paul Falstad and ported to the browser by Iain Sharp. It is redistributed here under the GPLv2 and is not our own work. Source: github.com/pfalstad/circuitjs1, licence: COPYING.txt.
IBIS model waveform simulator
Load an IBIS model (.ibs) and run a transient analysis of driver → package → PCB trace (transmission line) → termination → receiver, showing the waveform at both ends. See how reflections and ringing change with termination and trace length.
- Differential pairs (LVDS and similar) when the model has [Diff_pin], with Vod/Vos and eye diagram
- Change bit rate, bit pattern, termination scheme and trace length
- Nodal analysis with Newton-Raphson and backward Euler; transmission lines by Branin’s method
- Your .ibs file is processed in the browser and never uploaded