Design of Class E Power Amplifier with New Structure and Flat Top Switch Voltage Waveform

In this paper, a new topology of the class E power amplifier (PA) is proposed. The output circuit in the proposed PA is different from that in the conventional class E PA. The conventional output circuit of class E PA consists of shunt capacitor, resonant capacitor, resonant inductor, and shifting inductor. An additional shunt capacitance is added between the resonant capacitance and the shifting inductor to shape the reduced switch voltage. The peak switch voltage of the proposed class E PA is approximately 78% of that of the conventional one, which shows a reduction in peak switch voltage. The lower peak switch voltage reduces the breakdown voltage of the active device. Also, the proposed structure can introduce a new family of switching PAs with interesting specifications. Several values of switch voltage reduction and output power capability could be achieved by varying the circuit elements. Zero voltage and zero derivative switching conditions are achieved in the switch voltage of the designed circuit. The simulation of the proposed circuit is performed using PSpice software. For verification, the presented PA is fabricated and measured.