Patent ID: 6909394

Claim:
A quantizer for a sigma delta modulator having at least one input stage providing an input signal to the quantizer, the quantizer quantizing the input signal, in accordance with at least one threshold signal and outputting the quantized input signal as a digital result value at a digital result output of the sigma delta modulator, characterized in that the quantizer contains at least one quantizing cell wherein the number of quantizing cells corresponds to the number of the resolution levels of the quantizer, each quantizing cell having an input voltage/current converter for converting the input signal to be quantized into a corresponding input signal current; a static threshold current source is allocated to the at least one quantizing cell, the static threshold current source supplying a static component to the threshold signal in the form of a static threshold current wherein the quantizing cell comprises a dynamic feedback current source which generates an analog feedback current derived from the digital result value, wherein the analog feedback current is added to the static threshold current in a current node; wherein the threshold current is composed of the static threshold current and the feedback current is added to the input signal current in the current node; wherein the quantizing cell includes a comparison unit coupled to the current node for detecting whether the summed up current at the current node is not equal to zero and for outputting a digital quantizer cell result accordingly; and wherein the digital quantizer cell results form the digital result value.