Patent ID: 7049990

Claim:
A sigma-delta modulator comprising: a summing junction receiving an input signal; a plurality of integrators in series, the integrators outputting an integrated signal value to a multi-input quantizer; and wherein the multi-input quantizer has a plurality of comparators each with switched capacitor inputs, and wherein the multi-input quantizer outputs a quantized signal to a multi-bit feedback DAC whose output drives the summing junction and, wherein each comparator implements a function Y=A 1 *S 1 +A 2 *S 2 +A 3 *S 3 +A 4 *S 4 +, . . . where Y is the output of the comparator, A 1 , A 2 , A 3 . . . are constants, and S 1 , S 2 , S 3 . . . are input voltages.