Pulse Width Modulation

Contributors: JordanDee
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What is Pulse-width Modulation?

Pulse Width Modulation (PWM) is a fancy term for describing a type of digital signal. Pulse width modulation is used in a variety of applications including sophisticated control circuitry. A common way we use them here at SparkFun is to control dimming of RGB LEDs or to control the direction of a servo. We can accomplish a range of results in both applications because pulse width modulation allows us to vary how much time the signal is high in an analog fashion. While the signal can only be high (usually 5V) or low (ground) at any time, we can change the proportion of time the signal is high compared to when it is low over a consistent time interval.

Two servo motors used to control the pan/tilt of a robotic claw with PWM

Robotic claw controlled by a servo motor using pulse-width modulation

Suggested Reading

Some background tutorials you might consider first: