COMPARISON DEVICE AND METHOD THEREOF, ANALOG/DIGITAL CONVERSION DEVICE CAPABLE OF UTILIZING THIS COMPARISON METHOD, AND DETERMINING DEVICE USABLE FOR THIS COMPARISON METHOD

摘要

PROBLEM TO BE SOLVED: To provide a technique for reducing power consumption of a comparison device or an AD converter by supplying power only to a necessary comparator. SOLUTION: The AD conversion device 1 includes a plurality of comparators for comparing an input analog signal with a predetermined reference value. The device 1 is provided with AD conversion circuits 12 each converting the input analog signal into a digital value of predetermined bit number utilizing comparison results of the plurality of comparators; determining circuits 20 each determining a region to which a voltage value of the input analog signal belongs before the comparators compare the input analog signal with the reference voltage; and control units 22 each controlling the supply of power for the plurality of comparators, depending on the region determined by the determining circuit 20. COPYRIGHT: (C)2005,JPO&NCIPI