Reply by robert bristow-johnson May 22, 20072007-05-22
On May 22, 9:10 pm, Tim Wescott <t...@seemywebsite.com> wrote:
> somdeb wrote: > > I am trying to understand how bit-width requirements at different > > integrators can be estimated... couldn't find much in literature.
...
> > As a guess, I'd say it has to be big enough so that, at a minimum, the > quantization noise from your integrator is insignificant compared to the > noise you expect to be getting from the modulator.
my guess is that quantization in the integrator is not the issue, but saturation. the first integrator is an up-down counter. if you assume your input is not pinned against the rails, how high (or low) does that up-down counter get? the base-2 log of that minus 1 is the bit width you need. the second integrator sums the output of the first and we ask the same question regarding it. that's my amateurish spin on it. r b-j