MASH modulator with digital correction for amplifier finite gain effects and C-ratio matching errors

Authors

Alan J. Davis, Naval Undersea Warfare Center Division Newport
Godi Fischer, Naval Undersea Warfare Center Division Newport

Document Type

Conference Proceeding

Date of Original Version

12-1-1997

Abstract

An alternative approach to remove the effects of amplifier finite gain and C-ratio mismatches encountered in a MASH delta-sigma modulator is presented. By adding a digital correction term to the output of the digital noise cancellation filter, the parasitic quantization noise terms can be removed for all but the final stage, eliminating the lower-order quantization noise terms due to non-ideal integrators. Using this technique, the MASH can approach the performance of an ideal 3^rd order modulator. We have confirmed an SNR+THD of 105.6 dB via a behavioral simulation of the MASH using an amplifier open-loop gain of only 500 and capacitor matching errors as large as of 1.0%.

Publication Title, e.g., Journal

Midwest Symposium on Circuits and Systems

Volume

1

Citation/Publisher Attribution

Davis, Alan J., and Godi Fischer. "MASH modulator with digital correction for amplifier finite gain effects and C-ratio matching errors." Midwest Symposium on Circuits and Systems 1, (1997). https://digitalcommons.uri.edu/ele_facpubs/1609