The A/D conversion circuit may include A/D conversion units each of which converts input analog signals into digital signals, a switch unit that receives a first and second analog signals among the analog signals, the switch unit alternately switching output destinations of the first and second analog signals input in the same period to the A/D conversion units in each sampling cycle of the A/D conversion units; and an arithmetic unit that performs a differential operation between a result of addition of the digital signals output from the A/D conversion units to which the first analog signal is input and a result of addition of the digital signals output from the A/D conversion units which the second analog signal is input, the arithmetic unit outputting a third digital signal corresponding to a result of the differential operation.