There is provided with an A/D conversion apparatus which the first terminal receives a reference voltage signal, the single-ended to differential converter conducts single-ended to differential conversion on the reference voltage signal to obtain a first differential signal, the A/D converter conducts A/D conversion on the first differential signal based on the reference voltage signal to obtain a first digital signal, the digital circuit detects a DC offset which is a difference between the first digital signal and a digital signal, the second terminal receives an input signal, the single-ended to differential converter conducts single-ended to differential conversion on the input signal to acquire a second differential signal, the A/D converter conducts A/D conversion on the second differential signal based on the reference voltage signal to acquire a second digital signal, and the digital circuit subtracts the DC offset from the second digital signal to obtain a third digital signal.