if it is possible i need 10ms resolution ! is it possible?

 

Certainly it's possible. If you used a simple RC low-pass filter with a 2ms time-constant, (which would settle to within 1% of the final value in 10ms), the output ripple voltage of the filtered signal would be no more than 30mVpp with a 5V PWM input to the filter.

Is that satisfactory?

 

perfect! but i don't know how to design that filter !

 

perfect! but i don't know how to design that filter !

An RC filter with a 2ms time-constant can be made from any combination of R and C that multiply together to give 2ms. For example if you use 10kΩ for the resistor than you would use a value of 2ms/10k = 200nF for the capacitor. The value you use for the resistor depends upon the impedance of the circuit where the filter is placed. You want R to be a least 10 times smaller than the circuit impedance on the output (load) side of the filter and at least 10 times larger than the impedance of the source on the input side of the filter.

The resister is in series with the capacitor to ground for the low-pass filter response that you want.

 

thank you so much! it was very use full ! i have a perfect response with this new filter on my circuit ! thank you very much