An analog-to-digital converter circuit having a simple design and capable of preventing an increase in surface area and other problems. An analog-to-digital converter circuit for converting an analog input signal to a digital quantity includes an analog-to-digital converter unit that converts analog input signals to pre-correction digital values, and a corrector unit that digitally corrects the pre-connection digital values output from the analog-to-digital converter unit. The corrector unit includes a weighting coefficient multiplier unit that outputs a post-correction digital value obtained by multiplying the weighting coefficients provided for each bit by each bit of the pre-correction digital value output from the A/D converter unit and summing them, and a weighting coefficient search unit that searches for weighting coefficients so as to minimize an error signal generated based on the post-correction digital value and an approximate value for the post-correction digital value.