A semiconductor device comprising a rectifier circuit, wherein the rectifier circuit includes first and second input wires to which AC signals whose phases are inverted from each other are transmitted; a first transistor of a first conductive type which has a first power wire connected with a first transistor terminal and a gate connected with the first input wire; a second transistor of the first conductive type which has the first power wire connected with a first transistor terminal, and a gate connected with the second input wire; a third transistor of a second conductive type which has a second power wire connected with a first transistor terminal, a second transistor terminal connected with a second transistor terminal of the first transistor and a gate connected with the first input capacitor; and a fourth transistor of the second conductive type which has the second power wire connected with a first transistor terminal.