ANALOG-TO-DIGITAL CONVERTER AND SELF-DIAGNOSIS METHOD FOR ANALOG-TO-DIGITAL CONVERTER

An analog-to-digital converter includes an input terminal to which an analog input voltage is input, a digital-to-analog converter unit, a comparator that compares the analog input voltage and an output voltage of the digital-to-analog converter unit with each other, a successive approximation register that stores a conversion result output from the comparator, a generator unit that generates added digital data and subtracted digital data, the added digital data and the subtracted digital data being obtained by adding and subtracting the conversion result to and from the conversion result retained by the successive approximation register, respectively, and a determination unit that determines whether or not a failure is occurring, by using a result of the comparison between the analog input voltage and output levels obtained by the digital-to-analog converter unit converting the added digital data and the subtracted digital data.