What is duty cycle?
Duty cycle is the percentage of time a signal is HIGH within one period. A 50% duty cycle means the signal is on half the time. The average output voltage equals supply voltage multiplied by duty cycle.
PWM / Duty Cycle Calculator
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Waveform — 50.0% duty cycle
PWM duty cycle and frequency calculator for microcontroller projects
PWM for motor and LED control
PWM is used to control motor speed, LED brightness, and servo position. Arduino analogWrite uses 8-bit PWM (0–255) at ~490 Hz or ~980 Hz depending on the pin. The duty cycle maps directly to output power.
Choosing PWM frequency
Higher frequencies reduce ripple but increase switching losses. For LED dimming, any frequency above ~200 Hz avoids flicker. For audio amplifiers or filters, match the PWM frequency to at least 10× the signal bandwidth.