New electronic hobbyists are often confused with the term Pulse Width Modulation or PWM. The word looks a bit complicated, but I can assure you that understanding is definitely not that difficult.
Are you wondering What is Pulse Width Modulation?
To follow the term we need to understand it word by word, so lets begin with the word “Pulse” and understand what it stands for.
A pulse is a sudden rise and subsequent fall of a voltage from zero to a certain peak and back to zero. When a train or chain of this rise and fall of some specified voltage
Normally these pulses are rhythmic in nature having a fixed rise and fall time, controlled by an electronic system or a circuit. The distance between each pulse in the train usually has a specific time interval, controlled or set by the circuit through which it is generated.
This time interval for which the pulse in between two gaps or a gap in between two
subsequent pulses is maintained is called duty cycle, which is nothing but the width of the alternate pulses and the notches.
So now we also know what width of the pulses means.
Finally, the modulation means, controlling the above width of the pulses or the width of the gaps arising in between the pulses to a desired or predetermined time intervals.
So either the gap width can be increased making the pulses narrower or the pulse width may be increased making the gaps between them narrower and vice versa at a time.
This function is termed as PWM or Pulse Width Modulation.
There are many special ICs which can be configured for doing the PWM function, such as the IC 555, IC 3524 etc. The PWM control has many useful applications in the field of power control like in inverters, motor controls, robotics, SMPS Power supply etc.