Page 78 - Electronics Starter Kit_EN

Wiring diagram

20.4 PWM (Pulse width modulation)

We use PWM to control the speed of the motor or the brightness of an LED for example, it is a
square wave in a high frequency, there are two main values for PWM which are frequency, duty
cycle.

A duty cycle is the fraction of one period in which a voltage is high.

For example if you have 5V on the input, and the duty cycle is 0, so you will get 0V on the
output, but if the duty cycle is 25% you will get 1.25V on the output and so on.
In our case frequency will be constant, we are going to modify the duty cycle.

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