The first terminals of a plurality of resistor elements are connected to the intermediate connection points of a plurality of FETs connected in series, and a voltage, having a phase opposite to that of the voltage applied to the gate terminals of the plurality of FETs, is applied to the second terminals of the plurality of resistor elements. With this configuration, the potentials at the intermediate connection points of the plurality of FETs connected in series can be prevented from lowering. As a result, the power that can be handled can be increased. Furthermore, since the potentials at the intermediate connection points of the plurality of FETs connected in series can be prevented from lowering, the deterioration of the distortion characteristic and the isolation characteristic owing to the lowering of the potentials at the intermediate connection points of the plurality of field-effect transistors connected in series is prevented, and excellent high-frequency characteristics are obtained.