US 12,003,247 B2
Noise shaper variable quantizer
Francesco Stilgenbauer, Rho (IT)
Assigned to STMicroelectron S.r.l., Agrate Brianza (IT)
Filed by STMicroelectronics S.r.l., Agrate Brianza (IT)
Filed on Jun. 22, 2022, as Appl. No. 17/846,520.
Prior Publication US 2023/0421167 A1, Dec. 28, 2023
Int. Cl. H03M 1/06 (2006.01); H03M 3/00 (2006.01)
CPC H03M 1/0668 (2013.01) [H03M 1/0626 (2013.01); H03M 1/0648 (2013.01); H03M 3/492 (2013.01); H03M 3/51 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A signal processing circuit, comprising:
a transmitter section including a noise shaper, the noise shaper comprising:
a filter receiving a noise shaping input signal and a quantizer output signal, the filter configured to generate a quantizer input signal based at least upon the noise shaping input signal and the quantizer output signal; and
a quantizer receiving the quantizer input signal and configured to divide the quantizer input signal by a first scaling factor to produce a noise shaping output signal, and to multiply the noise shaping output signal by the first scaling factor to produce the quantizer output signal;
a receiver section including:
receiver circuitry receiving the noise shaping output signal, the receiver circuitry configured to scale the quantizer output signal by a second scaling factor; and
a dynamic range optimization circuit configured to:
determine whether an absolute value of the noise shaping input signal is less than a threshold value;
lower the first scaling factor in response to the absolute value of the noise shaping input signal being less than the threshold value; and
decrease the second scaling factor in response to the absolute value of the noise shaping input signal being less than the threshold value, proportionally to the lowering of the first scaling factor, such that a ratio between the first scaling factor and the second scaling factor remains substantially constant.