Patent ID: 8947287
Filing Date: 2015-02-03
Classification: H03M

Abstract:
1. An A/D converting method for converting an analog input voltage into digital data, comprising: a first step in which the input voltage is compared with a plurality of threshold voltages, and judgment is made regarding which one from among a plurality of segments the input voltage belongs to; a second step in which a first voltage and a second voltage are generated such that the segment to which the input voltage belongs is sandwiched between the first voltage and the second voltage; a third step in which a third voltage is generated by amplifying the difference between the first voltage and the input voltage with a predetermined common voltage as a base; a fourth step in which a fourth voltage is generated by amplifying the difference between the second voltage and the input voltage with the common voltage as a base; a fifth step in which a region between the third voltage and the fourth voltage is divided into a plurality of segments, and judgment is made regarding which one from among the plurality of segments the common voltage belongs to; a sixth step in which a fifth voltage and a sixth voltage are generated such that the segment to which the common voltage belongs is sandwiched between the fifth voltage and the sixth voltage; a seventh step in which a seventh voltage is generated by amplifying the difference between the fifth voltage and the common voltage with the common voltage as a base; and an eighth step in which an eighth voltage is generated by amplifying the difference between the sixth voltage and the common voltage with the common voltage as a base, wherein the fifth step through the eighth step are repeatedly executed, and wherein, when the flow returns from the eighth step to the fifth step, the seventh voltage obtained in the seventh step in the previous loop is used as the third voltage in the fifth step in the subsequent loop, and the eighth voltage obtained in the eighth step in the previous loop is used as the fourth voltage in the fifth step in the subsequent loop.