Duty cycle is the ratio of the pulse duration to the total period of a waveform, usually expressed as a percentage. In a digital clock, a 50 percent duty cycle means the signal is high for exactly half the time and low for the other half. In power electronics, adjusting the duty cycle of a pulse-width modulated (PWM) signal controls the average power delivered to a load, such as a motor or an LED.
If the motor is running too fast, drop the PWM duty cycle down to 30 percent.
Related terms
PWM
Pulse-width modulation is a technique for controlling average power delivery by rapidly switching a signal on and off.
Pulse
A rapid, transient change in voltage or current from a baseline value and back again.
Clock
A continuous square wave signal that synchronizes the timing of digital circuits.
Off time
The portion of a switching cycle where a device is turned off and no current flows.