Patent ID: 8994572
Filing Date: 2015-03-31
Classification: H03M

Abstract:
1. A cyclic-type analog-digital converter for converting an analog input signal that is input into a digital signal having a predetermined resolution, the analog-digital converter comprising: a digital approximator including a comparator configured to compare the magnitude of a first analog signal that is input and a threshold value and to output a digital value indicative of the comparison result and a multiplying digital-analog converter configured to amplify the first analog signal by a factor of β and at the same time, to perform a predetermined calculation in accordance with the comparison result of the comparator to output a second analog signal; a multiplexer configured to output an analog input signal as the first analog signal when calculating the most significant bit and to output the second analog signal as the first analog signal when calculating a bit other than the most significant bit; a β estimator configured to estimate the value of β; and a digital signal output unit configured to sequentially take in the digital value output from the comparator and to output the digital value as a digital signal based on an estimated value of β, wherein the value of β is a value larger than 1 and smaller than 2.