Pulse Width Modulation (PWM)

1. Definition

PWM (Pulse Width Modulation) is a technique used to control the amount of power delivered to electronic devices.
Instead of changing voltage directly, it rapidly switches the signal ON and OFF at high speed, and the ratio of ON-time to OFF-time determines the effective output.

PWM signal example

Duty Cycle: The percentage of time the signal is ON compared to the total cycle time.

  • 0% Duty Cycle → Always OFF
  • 50% Duty Cycle → ON half the time
  • 100% Duty Cycle → Always ON

2. Applications

  • LED Dimming: Control brightness smoothly.
  • Motor Control: Adjust speed without extra heating.
  • Sound Generation: Create tones using different frequencies.
  • Power Regulation: Efficient control of voltage and power to devices.

3. How it Works

  • A digital pin switches between HIGH (ON) and LOW (OFF).
  • The switching happens very fast (thousands of times per second).
  • The device (LED, motor, etc.) perceives it as a variable power level instead of flickering.

4. Video Explanation

Video coming soon