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Topic: Advantage of higher frequency PWM? (Read 83 times) previous topic - next topic

DrBwts

Hi

I'm using a lot of PWM on a Mega 2560 at the moment & have noticed that quite a few people are asking for higher frequency PWM than the default 490Hz used by the analogWrite() fundction.

What is the advatage of using highr frequencies? I've noticed 10KHz seems a common asked for value but so far havent fund a ood reason why this would function better than 490Hz.


MarkT

Well it reduces flicker in LEDs, and for motor control is strongly affects the decay time and thus
response to duty-cycle.
For motors the audible whine due to PWM can be pushed to 20kHz or higher out of the range
of hearing.
For power conversion higher frequencies mean less energy stored per cycle, meaning smaller
capacitors and inductors.
[ I will NOT respond to personal messages, I WILL delete them, use the forum please ]

Wawa

Well it reduces flicker in LEDs...
It might reduce the (already invisible to humans) flicker in LEDs.
It definately reduces the ability to dim to the extremes.
1/256 of the pulse time of 10kHz is too short for most constant current dimmers or pin driven mosfets.
Leo..

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