Pulse Width Modulation

Pulse-width modulation (SIM) ( English pulse-porosity modulation, PPM ) - a type of pulse modulation, in which the duty cycle of rectangular pulses varies according to the law of the modulating signal and does not depend on the frequency of the reference signal. Pulse-width modulation differs from pulse-width and pulse-frequency modulations in that, for example, with a constant modulating signal, the duty cycle of the output sequence of rectangular pulses is kept constant when the reference frequency changes. This property is reflected in the name of this type of pulse modulation.