Patent ID: 6956516

Claim:
An A/D-conversion circuit that converts an analog voltage to a digital value to be outputted, comprising: a counter that outputs a count value; a first voltage generation circuit that generates a first analog voltage, which monotonically increases or decreases; a comparator that compares the first analog voltage from the first voltage generation circuit with a second analog voltage, to which A/D conversion is applied, and outputs an output signal according to a comparison result; a digital filter circuit that receives the output signal from the comparator, executes digital filtering for the output signal from the comparator, and outputs an output signal, for which the digital filtering has been executed; and a count value hold circuit that receives the output signal from the digital filter circuit and the count value from the counter, and that holds the count value from the counter based on the output signal from the digital filter circuit, and outputs a held count value as the digital value.