A complex power management device includes DC/DC converters and a common reference line connected in common to the DC/DC converters. Each of the DC/DC converters includes a first switch element and inductor connected in series between first and second nodes, a second switch element, one end of which is connected to a third node that is a connection point of the first switch element and the inductor and the other end of which is connected to the corresponding ground terminal, and an output voltage adjustment circuit, which exclusively controls an ON/OFF state of the first and second switch elements based on a voltage of a fourth node that is the other end of the second switch element. The common reference line is connected to a fifth node that is provided on a wire connecting the second switch element of each of the DC/DC converters to the ground terminal.