Patent ID: 8466821
Filing Date: 2013-06-18
Classification: H03M

Abstract:
1. A delta sigma analog-to-digital converter for performing delta sigma analog-to-digital conversion, comprising: an operational amplifier that integrates a feedback signal and a time-divisionally combined signal that is obtained by time-divisionally combining M signal sequences (M is an integer of 2 or more); M integral capacities; a switch that controls selection of an integral capacity for use, from among the M integral capacities in accordance with a selection signal; a comparing section that encodes and converts, into a code value, an integration result provided by an integration processing section formed by the operational amplifier and the integral capacity selected by the switch; a storage section that stores respective M code values for the M signal sequences; a selection section that selects one of the M code values stored for the M signal sequences, in accordance with the selection signal; and a digital-to-analog converter that converts, from digital to analog, the selected code value and generates the feedback signal, wherein: the comparing section encodes and converts the integration result at a first rate; a specific one of the M signal sequences is time-divisionally combined at a second rate in the time-divisionally combined signal; the switch selects a specific one of the M integral capacities for use at the second rate; and the second rate is lower than the first rate/M.