PWM Duty Cycle Calculator
Calculate PWM duty cycle percentage and frequency from on-time and off-time.
Essential for motor control and LED dimming.
Duty Cycle & Frequency
PWM (Pulse Width Modulation) switches a signal on and off rapidly to control average power.
Duty Cycle: D = (T_on / T_total) × 100%
Frequency: f = 1 / T_total
Where T_total = T_on + T_off
Key relationships:
- Higher duty cycle = more average power
- 0% duty cycle = always off
- 50% duty cycle = on half the time
- 100% duty cycle = always on
Common applications:
| Application | Typical Frequency |
|---|---|
| LED dimming | 500–1,000 Hz |
| Motor control | 1–20 kHz |
| Servo control | 50 Hz |
| Switching PSU | 50–500 kHz |
| Audio (Class D) | 200–400 kHz |