PWM API

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Pulse Width Modulation (PWM) is the technique of generating a rectangular pulse wave that has a pulse width that is modulated to result in the variation of the average value of the waveform. Most common uses include driving servo motors, dimming LEDs, or other related functions. PWM is intended to be used primarily for Internet of Things scenarios.

About Pulse Width Modulation

A PWM waveform can be categorized by two parameters:

• A waveform period (T)

• The duty cycle, where the waveform frequency (f) is the reciprocal of the period f=1/T

The duty cycle describes the proportion of the on/Active time with respect to the regular interval or Period of time. A low duty cycle corresponds to an average of low output power, because the power is off for most of the time. Duty cycle is expressed as a percentage. Fully on is 100%. Fully off is 0%. Active half the time is 50%.

Developers looking to implement PWM in their IoT applications should investigate the WinRT PWM documentation.

Pulse Width Modulation types

PWM uses these IO control codes, structures, and enumerations.

PWM also uses the following function: PwmParsePinPath.