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naebad
10-09-2005, 09:30 PM
I have read a bit about oversampling. Understand most of the theory but
get stuck at the easy bit. If we sample with one a one bit ADC - how do
we get 16 bits back from this single bit to do the processing?

Naebad

Tim Wescott
10-10-2005, 06:35 AM
naebad wrote:

> I have read a bit about oversampling. Understand most of the theory but
> get stuck at the easy bit. If we sample with one a one bit ADC - how do
> we get 16 bits back from this single bit to do the processing?
>
> Naebad
>
The Sigma Delta ADC uses a one-bit ADC that's coupled to a one bit DAC
and integrator feedback. The feedback forces the low-frequency error of
the ADC signal to be low. Getting back to 16 bits (or 24) is simply a
matter of lots of low-pass filtering which can be done accurately and
cheaply in the digital domain, and is usually done inside the ADC.

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com