In the introduction we talked about the average value of a PWM signal. That average can be considered an analog value for the signal as long as the frequency is high enough that the circuits do not notice it. Many circuits will have voltage regulators to compensate for the variations on the input and in that case it will be in fact an analog output. This analog value is directly proportional to the duty cycle.
Since we only have one PWM available we will use a single color LED to visually understand how analog outputs work. In the case of the LED, the intensity of the brightness will be proportional to the value of the duty cycle.
We will use a red LED for this example, connected as shown in the following diagram. We connect the LED to the PWM pin, add a 330 Ω resistor to take care of the extra voltage, and then we connect again to ground. A mini breadboard...
