| 摘要 |
PROBLEM TO BE SOLVED: To shorten a conversion time.SOLUTION: A D/A conversion circuit 11 includes main capacitors CA4-CA0 and measuring capacitors CM2-CM0, and capacitance values of the main capacitors CA4-CA0 are equal to or less than a total value of capacitance values of lower-order main capacitors CA3-CA0. The D/A conversion circuit 11 generates an output voltage Vo corresponding to an analog input signal VIN. A comparator 12 compares the output voltage Vo with a common voltage VCM and outputs a determination signal Ka. A measurement control circuit 14 measures the capacitance values of the main capacitors CA4-CA2 on the basis of the determination signal Ka while using the lower-order main capacitors CA3-CA0 and the measuring capacitors CM2-CM0. A conversion control circuit 13 generates a digital signal Da by converting the analog input signal VIN on the basis of the determination signal Ka. A correction circuit 15 generates a digital output signal DOUT by correcting the digital signal Da on the basis of a capacitance value Wa measured by the measurement control circuit 14. |
