Patent ID: 7639164

Claim:
An output data correction device for correcting a non-linearity of an analog-to-digital (A/D) conversion circuit that converts an analog signal to digital data, the output data correction device comprising: a deciding means for deciding to which of a plurality of domains that an estimated maximum input range is divided a voltage input to the A/D conversion circuit belongs; a reference voltage designating means for selecting and transmitting at least three reference voltages associated with each of the plurality of domains; an input selecting means for selecting one of among an input voltage and the reference voltages as a signal to be input to the A/D conversion circuit; a correctional equation determining means for computing and determining a respective n-th order functional equation when the input selecting means selects each of the reference voltages, the respective n-th order functional equation having a graph that passes through a coordinate point associated with a respective one of the three or more reference voltages in a two-dimensional coordinate system in which the axis of ordinates indicates reference voltages and the axis of abscissas indicates values of digital data converted by the A/D conversion circuit; and a correcting means for correcting the converted digital data using the respective n-th order functional equation associated with a domain to which the input voltage is decided to belong by the deciding means, when the input selecting means selects the input voltage,.