Mismatch shaped analog to digital converter

A noise-shaping analog to digital converter comprising:

• a first circuit for providing a plurality of reference voltages;
• a plurality of comparators adapted to compare an input signal with said reference voltages;
• a router adapted to connect said reference voltages to said comparators in accordance with one or more control signals;
• and
• a noise-shaping circuit adapted to generate said control signals such that noise caused by mismatch errors is spectrally shaped according to a desired noise-shaping characteristic.

A multi-bit Delta-Sigma modulator comprising:

• a summing circuit for generating a difference signal from an input signal and a feedback signal;
• a filter adopted to receive said difference signal and output a filtered signal;
• a circuit for generating a plurality of reference voltages;
• a plurality of comparators adapted to compare said filtered signal with said reference voltages and output a plurality of digital output signals;
• a digital to analog converter adapted to convert said digital output signals to analog to generate said feedback signal;
• a router adapted to connect said reference voltages to said comparators in accordance with one or more control signals;
• and
• a noise-shaping circuit adapted to generate said control signals such that noise caused by mismatch errors in said digital to analog converter is spectrally shaped according to a desired noise-shaping characteristic.

A method for spectrally shaping noise due to mismatch errors in a multi-bit Delta-Sigma modulator including the steps of:

• generating a difference signal from said input signal and a feedback signal;
• filtering said difference signal to generate a filtered signal;
• generating a plurality of reference voltages;
• comparing said filtered signal with said reference voltages using a plurality of comparators to generate a plurality of digital output signals;
• randomizing connections between said reference voltages and said comparators such that noise caused by mismatch errors is spectrally shaped according to a desired noise-shaping characteristic;
• and
• converting said digital output signals to analog to generate said feedback signal.