What is the difference between pwm and digital

Yet, I can clearly remember the first time I took a picture with my old Kodak camera. That was almost two decades ago, and in , Kodak filed for bankruptcy as it failed to transition quickly and effectively enough into the era of digital photography. Somehow, this all reminds me of how important it is to be able to convert an analog signal to its pulse width modulation PWM counterpart. Because doing so requires—and affords—a similar flexibility to circuit design , and that is going to be the focus of this article.

Analog to PWM conversion can be confusing for those who are not familiar with the two technologies. PWM can be used to produce analog signals. However, analog signals are not PWM signals. Does that make sense? An analog signal is a continuous signal where there seems to be an unbroken continuity of its waveform over an infinite time period. A sine wave is an example of an analog signal. Meanwhile, PWM is a technique that changes the duty cycle of a digital signal.

PWM is usually sent as square waves and is commonly used for power transfer, servo motor control, and as a communication protocol. It can also be used to generate analog voltage by altering the duty cycle accordingly to the desired value.

A capacitor is then used to smooth the PWM waveform. We use duty cycle and frequency to describe the PWM, and we often talk about frequency in reference to speed. For example, a variable frequency drive motor produces a response like analog device in the real world. The separate pulses that the VFD motor gets are not discernable to us; as far as we can see, the pulses are so fast usually somewhere in the milliseconds that by real world standards it just seems like a motor ramping up.

The duty cycle can change to affect the average voltage that the motor experiences. The frequency of the cycles can increase. The pulse can even be increased in length. Pulse width is directly related to duty cycle, so if you decide to increase the width of a pulse, you are just altering the duty cycle. MCUs are digital. An example of something that can create a true analog output would be a transducer something that directly translates physical phenomenon to an analog signal.

Learn more. Asked 1 year, 1 month ago. Active 1 year, 1 month ago. Viewed times. Manzillo Manzillo 97 3 3 bronze badges. Using it in PWM mode to make a digital signal instead of just putting it back in its normal digital mode is over-complicating things. Add a comment. Active Oldest Votes. Most PWM outputs can be configured as digital outputs and directly switched on and off. Transistor Transistor k 11 11 gold badges silver badges bronze badges.

Sign up or log in Sign up using Google. Sign up using Facebook. Sign up using Email and Password. Post as a guest Name.