Patent ID: 6218975
Filing Date: 2001-04-17
Classification: H03M

Abstract:
An analog-to-digital converter, comprising:a plurality of chopper type comparators, each receiving a reference voltage and an analog voltage and performing an auto-zero operation for setting the reference voltage and a comparing operation for comparing the reference voltage set by the auto-zero operation with the analog voltage to output a comparison result signal, the comparing operation being performed a plurality of times subsequent to the auto-zero operation;a controller circuit, coupled to the plurality of chopper type comparators, controlling one comparator to perform the auto-zero operation and the remaining comparators to perform the comparing operations, substantially simultaneously, the controller circuit selectively outputting the comparison result signals output from the remaining comparators; andan encoder, coupled to the controller circuit, receiving the comparison result signals and generating a digital signal therefrom,wherein said controller circuit includes a signal selector circuit for switching a first comparison result signal output from a first comparator performing the comparing operation before or after the auto-zero operation to a second comparison result signal output from a second comparator performing the comparing operation using the same reference voltage as the first comparator.