Berti wrote on Oct 17th, 2007, 10:18pm:Hey,
consider the design of a tri-level quantizer instead of a 1bit quantizer. As long you make sure that the offset of the amplifier is always transfered,
a tri-level quantizer is inherently linear but drastically reduces quantization noise compared to 1 bit.
Regards
Hi Berti,
Could you please elaborate on this point? Why would a tri-level quantizer drastically improve quantization noise? If one purely considers
the number of quantization levels, not much has changed. Are you implying that the linearization of the quantizer characteristic allows larger
input signal without impairing stability, or is there some other reason? One reason I can see is that the presence of 3 levels would mean that the
quantizer output idles around the mid-level most of the time when the input signal is very small, thereby reducing the amount of out-ofband noise
that needs filtering, but this would not hold for larger signals.
Hi Pancho,
Also consider multibit quantizers and single-loop DSM. With mismatch shaping and dithering, you can get excellent performance and the design
is considerably simplified.
Regards
Vivek