| 摘要 |
PROBLEM TO BE SOLVED: To provide an A/D conversion circuit that A/D-converts an input signal with a wide dynamic range, and an electronic instrument including it. SOLUTION: The A/D conversion circuit includes: an amplifier circuit 10 that includes a plurality of amplifiers which are cascaded; a selector 20 that selects one of output signals AQ1-AQN of the plurality of amplifiers AM1-AMN and outputs it as a selector output signal ALQ; an A/D converter 50 that A/D-converts the selector output signal SLQ from the selector 20; a determination circuit 60 that determines whether or not a voltage of the output signals AQ1-AQN of each of the plurality of amplifiers AM1-AMN is within a determination voltage range specified by a high-potential-side determination voltage VCH and a low-potential-side determination voltage VCL; and a control circuit 70 that instructs the selector 20 to select one of the output signals AQ1-AQN of the plurality of amplifiers AM1-AMN based on the determination result of the determination circuit 60. COPYRIGHT: (C)2009,JPO&INPIT
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