Patent ID: 11611353

Abstract:
A quantizer for a sigma-delta modulator, a sigma-delta modulator, and a method of shaping noise are provided. The quantizer includes: an integrator configured to generate, in a Kth sampling period, a quantization error signal for a Kth period according to an internal signal, a quantization error signal for a (K−1)th period, a filtered quantization error signal for the (K−1)th period and a filtered quantization error signal for a (K−2)th period; an integrating capacitor configured to store the quantization error signal for the Kth period, to weight the internal signal in a (K+1)th sampling period; a passive low-pass filter configured to acquire the quantization error signal for the Kth period in a Kth discharge period, and feed back the filtered quantization error signal to the integrator in a (K+1)th sampling period and a (K+2)th sampling period; and a comparator configured to quantize the quantization error signal for the Kth period.