Duty cycle is a term commonly used in electronics and specifically in the context of pulse width modulation (PWM). It refers to the ratio of time a digital signal is in its active state (high or "on" state) to the total time of one period of the signal. Duty cycle is typically expressed as a percentage.
In pulse width modulation, a periodic waveform (often a square wave) is used to control the average power delivered to a load, such as a motor or an LED. The duty cycle determines how much time the signal is in the high state (usually represented as a logic "1" or a voltage level that represents "on") compared to the total time of one complete cycle.
The significance of duty cycle in pulse width modulation lies in its ability to control the average power delivered to the load. By varying the duty cycle, you can control the amount of time the signal is "on" or "off," effectively adjusting the average power delivered to the load. This is particularly useful in applications where you need to control the speed, intensity, or position of a device.
For example, in motor control, a higher duty cycle will result in a higher average voltage applied to the motor, causing it to spin faster. On the other hand, a lower duty cycle will reduce the average voltage, causing the motor to spin slower. In LED brightness control, increasing the duty cycle will make the LED appear brighter, and decreasing it will dim the LED.
By precisely adjusting the duty cycle at a high frequency, pulse width modulation allows for efficient and precise control of the output signal, making it a popular technique in various electronic applications.