AD CONVERTER

摘要

A successive approximation type AD converter includes: a comparator comparing an analog input signal and a DA-converted comparison code; and a control circuit. When an output of the comparator settles before a limit time period has passed since the comparator started a comparison operation, the control circuit updates the comparison code on the basis of the settled output of the comparator. When the limit time period has passed before the output of the comparator settles, the control circuit updates the comparison code not on the basis of the present output of the comparator.

主权项

1. A successive approximation type AD (Analog-to-Digital) converter comprising:
a DA (Digital-to-Analog) converter for making a DA conversion of a comparison code; a comparator for comparing an analog input signal and said DA-converted comparison code; and a control circuit for updating, when an output of said comparator settles before a limit time period has passed since said comparator started a comparison operation, said comparison code on a basis of the settled output of said comparator, and updating, when said limit time period has passed before the output of said comparator settles, said comparison code not on a basis of a present output of said comparator.