A Reduced Switch Voltage Stress Class E Power Amplifier Using Harmonic Control Network

Abstract

Abstract-In this paper, a harmonic control network (HCN)is presented to reduce the voltage stress (maximum MOSFET voltage) of the class E power amplifier (PA). Effects of the HCN on the amplifier specifications are investigated. The results show that the proposed HCN affects several specifications of the amplifier, such as drain voltage, switch current, output power capability (C p factor), and drain impedance. The output power capability of the presented amplifier is also improved, compared with the conventional class E structure. High-voltage stress limits the design specifications of the desired amplifier. Therefore, several limitations can be removed with the reduced switch voltage. According to the results, the maximum drain voltage for the presented amplifier is reduced and subsequently, the output power capability is increased about 25% using the presented structure. Zero-voltage switching condition (ZVS) and zerovoltage derivative switching condition (ZVDS) are assumed in the design procedure. These two conditions are essential for high efficiency achievement in various classes of switching amplifiers. A class E PA with operating frequency of 1 MHz is designed and simulated using advanced design system (ADS) and PSpice software. The theory and simulated results are in good agreement.