Patent ID: 8692920

Claim:
An A/D converter for respectively converting a first analog signal and a second analog signal into digital data, comprising: an input terminal configured to input the first analog signal and the second analog signal in turn; a first capacitor and a second capacitor; a reference voltage line configured to connect to a reference voltage source; a reference signal line configured to connect to a signal source that generates a reference signal which changes temporally; a comparator which has a first input terminal and a second input terminal, and outputs an output signal according to a comparison result between an input voltage supplied to said first input terminal and a threshold voltage supplied to said second input terminal; and an output circuit which outputs digital data corresponding to a time from when the input voltage supplied to said first input terminal of said comparator begins to change until the output signal of said comparator changes, wherein the first analog signal, which is input to said input terminal in a state in which said input terminal and said reference voltage line are connected via said first capacitor, is converted into digital data when the reference signal is supplied to said reference signal line in a state in which said reference signal line and said first input terminal of said comparator are connected via said first capacitor, and wherein the second analog signal, which is input to said input terminal in a state in which said input terminal and said reference voltage line are connected via said second capacitor, is converted into digital data when the reference signal is supplied to said reference signal line in a state in which said reference signal line and said first input terminal of said comparator are connected via said second capacitor.