The duty cycle in electronics refers to the ratio of the time a signal is active (high) compared to the total time of one complete cycle. It’s often expressed as a percentage and is commonly associated with waveforms like pulse waves, square waves, and digital signals.
In the context of a periodic waveform, such as a pulse wave or a square wave, the duty cycle is calculated using the following formula:
[ \text{Duty Cycle} = \frac{\text{Pulse Width}}{\text{Period}} \times 100\% ]
- Pulse Width: The duration for which the signal is high (active).
- Period: The time it takes for one complete cycle of the waveform.
A duty cycle of 0% indicates that the signal is always low (inactive), while a duty cycle of 100% means that the signal is always high. A duty cycle of 50% indicates that the signal is active for half of the time and inactive for the other half.
For example, consider a square wave with a pulse width of 2 milliseconds and a period of 5 milliseconds. The duty cycle would be:
[ \text{Duty Cycle} = \frac{2 \, \text{ms}}{5 \, \text{ms}} \times 100\% = 40\% ]
Duty cycle is a crucial parameter in various applications, especially in pulse-width modulation (PWM) where it’s used to control the average power delivered to a load by varying the width of pulses. It’s also important in digital circuits, signal processing, and various electronic systems where signal timing and power management are critical.