From: "alan smith" <micro_eng2@yahoo.com>

>I have a 15.5KHz PWM being provided to me, where of course the duty cycle=
=20
>will adjust the "dc" value ranging over the 3.3V output of the device. So=
=20
>what is the optimum values for the RC filter....calculate >at a 50% duty=20
>cycle, or does it even matter? Just use 64.5uSec (roughly) and find some=20
>values to fit that ?

The optimum filtering depends on your required reponse time. For a simple R=
C=20
filter you will want a time constant of at least several (10?) times the=20
64.5 uSec you mention. The quicker the filter the more ripple you will see=
=20
in the output voltage.

-- Bob Ammerman
RAm Systems

--=20
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