Provided is a technique for effectively implementing DC removal during switching of transmission scheme or transmission data in a wireless apparatus equipped with a function for supplying a voltage to a power amplifier by ET control. When the ET control is not carried out in a power supply unit, more specifically, when an IQ signal is not present, a control unit outputs a pulse width modulation (PWM) signal for a fixed voltage via a switch unit. In other words, the switch unit selectively supplies a PWM signal for ET and a PWM signal for the fixed voltage to a switching amplifier. The switching amplifier is controlled by a predetermined control signal from the control unit.