Patent ID: 7456771
Filing Date: 2008-11-25
Classification: H03M

Abstract:
1. A sigma-delta modulator, comprising: an adder for receiving an input signal and an analog signal, and generating a processed signal; a filter for receiving the processed signal and analog a filtered signal, comprising: at least one integrator for outputting at least one integration signal; at least one gain amplifier for amplifying the at least one integration signal to generate at least one amplified integration signal according to at least one default weighting coefficient assigned to each of the at least one gain amplifier; and a second adder for receiving and summating the at least one amplified integration signal and outputting the filtered signal; a quantizer for receiving the filtered signal to generate an output signal, wherein the quantizer operates in accordance with a first voltage difference; and a digital-to-analog converter for generating the analog signal according to the output signal, wherein the digital-to-analog converter operates in accordance with a second voltage difference; wherein the first voltage difference is K times of the second voltage difference and the at least one gain amplifier further amplifies the at least one integration signal by K times according to the first voltage difference and the second voltage difference, and K is smaller than 1.