Analog-to-digital conversion circuit

摘要

Digital signals of the most significant bit to the least significant bit are supplied to a digital calibration operation unit from a redundancy correction circuit, and an intermediate high order 2-bit digital signal is supplied to a correction value selection circuit. A DC control signal is supplied to the correction value selection circuit. A plurality of groups of correction values corresponding to the values of the intermediate high order 2-bit digital signal are stored in advance in a correction value ROM. The correction value selection circuit reads out a correction value from the correction value ROM based on the DC control signal and the intermediate high order 2-bit digital signal. The digital calibration operation unit adds the correction value AM to the digital signals of the most significant bit to the least significant bit, and outputs a resulting value as a digital output value.