| 摘要 |
PROBLEM TO BE SOLVED: To provide a D-A converter capable of suppressing increase in the number of switches, with increase in the number of bits and of preventing increase in area. SOLUTION: The D-A converter circuit includes a resistor string 190, a first selection circuit 191, an amplifier circuit 192, a second selection circuit 193 and a third selection circuit 194. The resistor string 190 generates a plurality of voltages, including an upper limit voltage, a lower limit voltage and an intermediate voltage. The first selection circuit 191 selects and outputs a first voltage among the plurality of voltages according to a lower bit, with the first voltage being equal to or lower than the intermediate voltage; and the second selection circuit 193 selects and outputs a second voltage among the plurality of voltages according to a higher bit, with the second voltage being either a voltage which is higher than the intermediate voltage or a lower power supply voltage. The third selection circuit 194 selects and outputs a third voltage according to the higher bit, with the third voltage being the lower limit voltage or the lower power supply voltage. The amplifier circuit 192 adds the first voltage and the second voltage, subtracts the third voltage and outputs an output voltage. COPYRIGHT: (C)2011,JPO&INPIT
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