Patent ID: 9735801
Date: 2017-08-15
CPC Classifications: H03M

Claim:
1. A sigma-delta modulator, comprising: a plurality of quantizers configured to produce a plurality of quantized signals; an input path configured to lead an input signal to the plurality of quantizers; a feedback path configured to feed back a feedback signal into the input path, the feedback signal produced by averaging the plurality of quantized signals; a loop filter put on the input path before the plurality of quantizers, the loop filter configured to receive the input signal and the feedback signal; a pre-filter configured to output a signal to a corresponding quantizer which is one of the plurality of quantizers, the pre-filter put on the input path between the loop filter and the corresponding quantizer, and the pre-filter configured to receive one of the quantized signals that is output from one of the plurality of quantizers which is different from the corresponding quantizer; a connection path configured to lead the quantized signal from the quantizer which is different form the corresponding quantizer to the pre-filter, and the connection path configured not to touch the feedback path.