Patent ID: 7361827

Claim:
A transducer for converting a physical quantity of a moving object to a digital signal representative of said physical quantity, comprising: a gain controller varying a potential range of an analog signal representative of said physical quantity expressing motion of said moving object; a converter monitoring said moving object, and causing said analog signal to swing a potential level in said potential range depending upon said physical quantity; an electric circuit connected to said converter, introducing an offset voltage into said analog signal, and producing said digital signal on the basis of said analog signal; and a calibrator connected to said gain controller and said electric circuit, causing said gain controller to change said potential range between a first range and a second range so as to determine an offset value corresponding to said offset voltage on the basis of said digital signal produced in said first range and said digital signal produced in said second range, and adding said offset value to said digital signal so as to output a calibrated digital signal.