AVR-Chat

Jim Wagner wrote:

>Each has its place.
>R-2R networks take much less filtering. Response speed is
>faster. Parts count is higher and it may take parts with
>some precision.
>PWM is (often) low parts count UNLESS you try to
>reconstruct signals that are too close to the PWM
>repetition frequency. Then, you can need multiple-pole
>filters that require op-amps or more.
>
>  
>
  Sure, but on the other hand, if you need to rresort to complex and 
expensive mutlipole filters, you're probably trying to reconstruct 
compelx signals with a processor that is poorly chosen for the task 
(e.g., isn't fast enough).  Moreover, if your signals are so compl;ex 
that multippole filters are needed, in all probabilty, you should be 
working a a greater resoltion than 8 bits to begin with.

  Of course, some of the AVRs, IIRC, can support up to 10 bit PWM (still 
pretty low resolution for fancy signal porocessing,though).

Tom