1 kW MHz Wideband Class E Power Amplifier

Abstract

Class E power amplifiers are widely used in highfrequency applications due to their simplicity and use of only one ground-referenced switch. However, Class E power amplifiers are usually tuned to operate at a fixed frequency due to their resonant nature. Extending the bandwidth of these switch-mode power amplifiers is beneficial in many applications, such as plasma generators and wireless power transfer systems. In this paper, we present a 1 kW wideband Class E power amplifier using Silicon Carbide (SiC) MOSFETs that achieves 93% efficiency at 13.56 MHz with a bandwidth of ±1 MHz. We incorporate a reactance compensation network in the output loading stage to achieve wideband operation; design a custom gate drive circuit to reduce the gate power loss and improve thermal performance compared to using a gate driver IC. The total gate power of one SiC MOSFET is measured to be 1.55 W at 13.56 MHz.

A Classification and Comparative Overview of CMOS Radio-Frequency Power Amplifiers

“…These requirements may be satisfied utilizing the network at output in Figure 11(b), as illustrated. According to an analytical derivation, the capacitors (C1,C2) and inductor (L1,L2)in a class-E design must have the succeeding values to meet the criteria at device turn-off [22]:…”

“…Using a large voltage to turn on and off the output transistor and a perfect square wave on the output load, the power at output of a class-F PA is [25]: (22) and the power capability is:…”

“…The duty cycle of the positive switching transistor is raised to produce the positive half of the waveform. At switching frequencies higher than 250 kHz, the Class-I amplifier is known alternatively as a "interleaved PWM amplifier" due to the interleaved behaviour of the two switching signal currents at the output [22], [27].…”

Frequency-Selective MHz Power Amplifier for Dielectric Barrier Discharge Plasma Generation

“…In this design, Q S is selected to be 2.5 to provide a bandwidth that covers the targeted operating frequencies. Next, L P and C P are calculated based on the reactance compensation requirement following the equations below: [22] C…”