[Solved] Difference between Hardware and Software PWM.

[Richu Bini]

What is the difference between hardware pwm and software pwm

[kowshik1729]

@Richu-Bini thanks for posting the question . just for a brief about pwm, pulse width modulation technique is a method to change the duty cycle of a wave. Which means you can determine how much time a signal must be on or off.

So, coming to the question, software pwm and hardware pwm is just two different ways of producing same result. In software(referring Arduino here) you'll just write a value between 0 to 255 inorder to determine duty cycle percentage. For example 0 is 0% duty cycle which means the cycle is on for 0% of whole time, similarly 127 means 50% of time cycle will be on and 255 means signal will be on for ever. This is regarding software.

Coming to hardware, you can generate a pwm signal using very simple passive component, called as potentiometer and 555 timer IC by using 555 timer as bistable multivibrator(The generated output will have two stable states 0 and Vmax, hence the name bistable) and changing the resistance using a potentiometer generates different duty cycles. This is the difference between hardware and software pwm. Please let me know if I haven't explained what you have expected.

[Richu Bini]

thank youu