A high-speed, high-resolution column A/D converter having a noise reduction function to eliminate a fixed pattern noise etc. is provided with a small circuit scale. Each column A/D converter includes a dual-output D/A converter for selecting two reference voltages from among a reference voltage group supplied in common to each column A/D converter, so as to output the two reference voltages to sandwich each sensor signal voltage input to each column A/D converter, along with a charge-redistribution D/A converter having a full scale determined by the above two reference voltages. Thus, the high-speed, high-resolution column A/D converter is achieved with a small circuit scale. Further, by the utilization of high-speed conversion capability, noise reduction is performed through digital calculation after the A/D conversion.