Important Parameters Associated with PWM Signal

An analog circuit can be controlled using digital pulses produced by a PWM signal. The behavior of a PWM signal is determined by these factors:

Duty Cycle of PWM

The fraction of a second that a signal or system is operational is called a duty cycle. A duty cycle is usually expressed as a percentage or ratio. The amount of time a signal takes to complete an ON-OFF cycle is called a period. The proportion of time a digital signal is on throughout a period of time or interval is precisely described by the percentage duty cycle. The waveform’s time is equal to its inverse frequency.

Duty Cycle : On Time / On Time + Off Time

We would say a digital signal has a 50% duty cycle and looks like a perfect square wave if it is on for half of the time and off for the other half. The digital signal spends more time in the high state than the low state if the percentage is greater than 50%, and vice versa if the duty cycle is lower than 50%. Here is a graph depicting the three scenarios.:

A 100% duty cycle is equivalent to a 5 volt (high) voltage setting. Grounding the signal would be equivalent to 0% duty cycle.

Frequency of PWM

The Speed at which something occurs over a specific time period is known as its frequency. In another way, the rate at which a vibration occurs that results in a wave, such as radio, light, or sound waves; this rate is usually measured in seconds.It is easy to define a frequency or period for regulating a particular servo.

Data is currently transmitted over communication channels using PWM’s duty cycle in an unambiguous communication system. PWM serves as a technique for converting high-frequency pulses into low-frequency output signals.

Frequency : 1 / Time Period

Output Voltage of PWM signal

It is the percentage of the duty cycle and can be calculated in that way only by calculating its percentage also. Let’s say the duty cycle is 100% then the output voltage will be 5V.

In Electronic Engineering, Pulse Width Modulation, or PWM, is a commonly used technique for effectively controlling the power supplied to electrical devices. In order to attain a desired average voltage or power level, the principle of pulse width modulation (PWM) is used for a periodic signal, which is usually a square wave.

A key component of pulse width modulation (PWM) is the duty cycle, which is defined as the ratio of the pulse width to the whole time period. An increase in the duty cycle translates into an increase in average power output. Basically, PWM is used to obtain analog signals from digital services- for instance, the microcontrollers and it represents the amplitude of an analog signal input signal.