US Patent 7298306 Delta sigma modulators with comparator offset noise conversion

Quantizers of delta sigma modulators include comparators to quantize a quantizer input signal. Each comparator compares a respective reference signal to the quantizer input signal. A logic processing module determines a quantizer output signal based upon the comparison. During subsequent periods of time, a comparator offset converter alters “reference signal-to-comparator input terminal” associations to reroute respective reference signals from one arrangement of comparator input terminals of at least two (2) of the comparators to a different arrangement of comparator input terminals. The comparator offset converter can randomly alter the reference signal-to-comparator input terminal associations. The comparator offset converter can maintain a 1:1 reference signal-to-comparator input terminal relationship. By maintaining the 1:1 ratio of reference signal-to-comparator input terminal and randomizing the reference signal-to-comparator input terminal associations, the comparator offset converter effectively converts the comparator offset voltage nonlinearities into energies and frequencies that can be constructively processed and improve signal-to-noise ratios.