A chopper type DC-DC converter includes a voltage converting circuit, a comparative wave generating circuit, a comparator group, and a switch control circuit. The voltage converting circuit converts a first voltage into a second voltage. The comparative wave generating circuit generates first and second comparative waves such that the voltage range of the first comparative wave is different from the voltage range of the second comparative wave. The comparator group generates a first comparison result signal indicating a result of comparison between the first comparative wave and an error signal indicating an error between the second voltage and target voltage and a second comparison result signal indicating a result of comparison between the second comparative wave and the error signal. The switch control circuit controls the voltage converting circuit based on the first and second comparison signals. The comparative wave generating circuit includes first and second comparative wave generating circuits. The first and second comparative wave generating circuits respectively generate the first and second comparative waves based on different source voltage groups.