Electromagnetics & Circuits

Circuits Simulators

A focused Electromagnetics & Circuits hub for circuits tools, keeping related formulas, assumptions, and engineering checks together.

42 simulators

Adjacent categories

Controls & Robotics Energy Systems Optics & Photonics Classical Physics

Simulator list

AC Circuit Impedance Simulator — RLC Series/Parallel, Resonance & Bode Plot
Circuits
Calculate impedance, resonant frequency, Q-factor, and phase angle for RLC series/parallel circuits in real time. Visualize Bode plot and phasor diagram to intuitively u…
Series RLC Circuit Simulator — AC Impedance and Resonance
Circuits
A resistor R, inductor L and capacitor C are connected in series with an AC source. Sweep the frequency f and watch impedance |Z|, phase angle, resonance frequency f0 an…
ADC Quantization Noise & SNR Simulator
Circuits
Every analog-to-digital converter has to round a continuous voltage to one of 2^N discrete codes.
ADC Sampling Jitter SNR Simulator
Circuits
See how jitter erodes SNR at high input frequency through waveform samples, an SNR curve, and an error cloud.
Band-Pass Filter Simulator — Series RLC Resonance and Q-factor
Circuits
Real-time series RLC band-pass filter simulator. Get resonant frequency, Q-factor, bandwidth, gain and phase, with a live Bode plot and circuit waveforms.
Biosensor EIS (Electrochemical Impedance Spectroscopy) Simulator
Circuits
Compute the Randles equivalent circuit response for a label-free biosensor and watch the Nyquist semicircle plus Warburg tail update in real time.
BJT Amplifier AC Analysis (CE/CB/CC)
Circuits
Analyze BJT amplifier AC performance: voltage gain, impedance, and Bode plots for Common Emitter, Base, and Collector configurations. Compare key formulas.
RC Capacitor Charge/Discharge Simulator — τ=RC
Circuits
Simulate RC circuit charging/discharging. Adjust R, C, V₀ to instantly see exponential curves, time constant τ=RC, and key equations.
Circuit Builder — Ohm's Law & Series/Parallel Circuits
Circuits
Visualize and simulate circuits with real-time Ohm's Law calculations. See electron flow and compute voltage, current, resistance, and power instantly.
Crosstalk in Coupled Lines Simulator
Circuits
A tool for calculating the "crosstalk" that appears between two traces running side by side on a printed circuit board.
DC Circuit Simulator
Circuits
Set supply voltage and resistor values to analyze series/parallel circuits
Electromagnet Lifting Force Simulator
Circuits
Compute, in real time, how hard a current-carrying horseshoe electromagnet pulls on an iron plate.
High-Pass Filter Simulator — First-Order RC Filter Frequency Response
Circuits
Real-time first-order RC high-pass filter simulator. Get cutoff frequency, gain, phase and time constant, with a live Bode plot and AC-coupling waveform view.
Inductor & RL Circuit Transient Response Simulator
Circuits
Visualize I(t) and V_L(t) in real time for energizing, de-energizing, and AC steady-state modes. Automatically calculates time constant τ, energy storage, reactance, imp…
Kirchhoff Laws Simulator — Series-Parallel Resistor Circuit
Circuits
A voltage source V feeds R_1 in series with the parallel combination of R_2 and R_3. The simulator visualizes the Kirchhoff voltage (KVL) and current (KCL) laws in real …
LC Circuit Oscillation Simulator — RLC Damped Oscillation
Circuits
Adjust L, C, and R to instantly visualize the damped voltage waveform and impedance resonance curve of an RLC circuit. Resonant frequency, Q factor, and decay time const…
LED Series Resistor Calculator
Circuits
Free LED current-limiting resistor calculator. From V_s, V_f, I_f and series count: ideal R, nearest E12 value, real current, resistor power and efficiency live.
Low-Pass Filter Simulator — First-Order RC Filter Frequency Response
Circuits
Real-time first-order RC low-pass filter simulator. Get cutoff frequency, gain, phase and time constant, and inspect the live Bode plot and circuit waveforms intuitively.
Magnetic Circuit & Reluctance Simulator
Circuits
Solve the magnetic flux flowing through the iron core of an electromagnet or inductor as a magnetic circuit built from reluctances.
Ohm's Law & DC Circuit Simulator — Voltage, Current, Resistance
Circuits
Interactive simulator to visualize Ohm's Law. Adjust voltage, current, and resistance in real-time, then analyze series and parallel DC circuits.
Op-Amp Circuit Simulator — Inverting, Integrator, Differentiator
Circuits
Visualize and simulate inverting, non-inverting, summing, and other key op-amp circuits in real time. See gain, phase shift, and waveforms instantly.
Op-Amp Circuit Simulator
Circuits
Visualize and simulate inverting, non-inverting, summing, and other key op-amp circuits in real time. See gain, phase shift, and waveforms instantly.
LC/RC Oscillator Design Calculator
Circuits
Calculate oscillator frequencies for Colpitts, Hartley, Clapp, Wien Bridge, RC Phase Shift, and Crystal circuits with real-time formulas and criteria.
Phase-Locked Loop (PLL) Simulator
Circuits
Design a phase-locked loop (PLL) that synthesises a high, accurately-spaced frequency by multiplying a clean reference by the divider ratio N.
Poynting Vector Simulator — Plane Wave Power Flux
Circuits
The Poynting vector simulator computes the instantaneous and time-averaged intensity of a plane electromagnetic wave in vacuum from E0, frequency, position and time.
RC/RL Circuit Transient Response Analyzer
Circuits
Analyze RC/RL circuit transient response instantly with our . Visualize voltage and current over time. No sign-up required.
LCR Resonance Circuit Simulator — Impedance, Phase & Q-Factor Calculator
Circuits
Visualize impedance and phase frequency response for series and parallel LCR circuits in real time. Instantly compute resonant frequency, Q-factor, and bandwidth.
UHF RFID Link Budget & Backscatter Distance Simulator
Circuits
Size up the communication range of a passive UHF RFID (EPC Gen2) deployment from reader EIRP, tag sensitivity, polarization loss, and frequency band. Forward and backsca…
RLC Circuit Resonance Simulator — Impedance, Q Factor & Bandwidth
Circuits
Interactive RLC circuit resonance simulator. Visualize impedance, current vs. frequency, and phasor diagrams. Calculate resonant frequency, Q factor, and bandwidth.
Schmitt Trigger Simulator
Circuits
Design a non-inverting Schmitt trigger that uses positive feedback to obtain two switching thresholds (hysteresis).
PN Junction Diode I-V Characteristic Simulator — Shockley Equation
Circuits
Simulate PN diode I-V curves with the Shockley equation. Adjust material, ideality factor, and temperature to explore semiconductor physics.
Shockley Diode Simulator — pn Junction I-V Characteristic
Circuits
Evaluate the Shockley diode equation I = I_S(exp(V/nV_T) - 1), the ideal current-voltage relation of a pn junction, in real time.
Sigma-Delta ADC Oversampling Noise Shaping SNR Simulator
Circuits
Pick the OSR, modulator order and quantizer bits of a ΣΔ ADC and see the in-band SNR, ENOB, sampling frequency and power update in real time. See for yourself how a sing…
NTC Thermistor Simulator — Resistance-Temperature Characteristic
Circuits
NTC thermistor simulator. Compute resistance, voltage-divider output and sensitivity from R0, B constant and temperature using the beta-parameter model in real time.
Thevenin Equivalent Simulator — Maximum Power Transfer
Circuits
A Thevenin source (V_th, R_th) feeds a wiring resistance R_w and a load R_L in series. Watch load current, voltage, power and efficiency update in real time and find the…
Total Harmonic Distortion (THD) Simulator
Circuits
Total harmonic distortion is the single number that measures how far an AC voltage or current waveform departs from a pure sine wave.
BJT Common-Emitter Amplifier Calculator — Operating Point, Gain & Load Line
Circuits
Calculate BJT common-emitter amplifier parameters: DC bias, voltage gain, and load line. Adjust VCC, resistors, and β in real-time.
BJT Transistor DC Bias Design
Circuits
Design BJT transistor DC bias circuits. Calculate Q-point, stability factor, and visualize the DC load line for voltage divider, emitter, and collector feedback bias.
Wheatstone Bridge Simulator — Balance Condition & Sensitivity
Circuits
Visualize the open-circuit output voltage Vout and balance condition of a bridge with four resistors R1 to R4 and excitation Vin. Experience the principle behind strain …
Wien Bridge Oscillator Simulator — Sinusoidal Oscillation Conditions
Circuits
Compute the Wien bridge oscillator frequency f0 = 1/(2*pi*R*C), the frequency-selective feedback ratio beta and the sustained oscillation condition A*beta = 1 in real ti…
Y-Delta (Star-Delta) Transform Simulator
Circuits
Convert three resistors between the Y (star) and Δ (delta) arrangements using the Kennelly transform. Useful for three-phase power, Wheatstone-style bridges, ladder netw…
Zener Voltage Regulator Simulator
Circuits
Design the simplest of all voltage regulators — a shunt regulator built from just a series resistor and a zener diode.

How to Use

  1. Select circuit topology (series, parallel, or mixed) using the cat-filter dropdown
  2. Input component values: resistor (Ω), capacitor (µF), inductor (mH), and source voltage (V) or current (A)
  3. Choose analysis mode: DC steady-state, transient response, or AC frequency sweep (1 Hz–1 MHz)
  4. Click Simulate to compute node voltages, branch currents, power dissipation, and impedance
  5. Export results as CSV for further analysis in SPICE or measurement validation

Worked Example

RC low-pass filter with R = 1 kΩ, C = 100 nF, Vin = 5 V DC. Cutoff frequency fc = 1/(2π×1000×100×10⁻⁹) = 1.59 kHz. At 1 kHz AC input, impedance Zc = 1/(2π×1000×100×10⁻⁹) = 1.59 kΩ. Voltage divider yields Vout ≈ 3.1 V with phase lag φ = −32°. Simulator confirms steady-state node voltage 3.1 V and reports 25 mW dissipation in resistor.

Practical Notes

  1. For stability: ensure time-step ≤ 0.1 × smallest RC or L/R time constant; transient overshoot in RLC circuits depends on damping ratio ζ = R/(2√(L/C))
  2. Verify Kirchhoff's voltage law (KVL) and current law (KCL) in mixed topologies; simulator flags violations
  3. In AC analysis, watch for resonance peaks when XL = XC; Q-factor = ωL/R determines bandwidth and selectivity
  4. Account for component tolerances (±5% resistors, ±10% capacitors) in sensitivity sweep mode