An analytical approach to the design and simulation of a Class-E power amplifier under typical high frequency switching conditions is presented. The analysis will optimize the loading network at the output for transistors with an exponential transition current, while accounting for harmonics injected into the circuit from the choke inductor and a non-infinite output Q. Two methods have been successfully implemented to simulate the class-E amplifier waveforms, optimize the required circuit components, and calculate amplifier performances such as efficiency and total harmonic distortion (THD). The first optimizes the circuit parameters while considering finite choke inductances, drain current fall time, and loaded quality factor of the output network inductance. The second accounts for all these in addition to a finite ON resistance of the switch, rise and fall time of the input signal, and parasitic resistances of both circuit inductors. The first method (integral method) utilizes an iterative technique where each waveform is defined symbolically and solved using the integral function in MATLAB. Initial values are assumed and an iterative process is implemented to quickly arrive at the desired results. The second method (finite difference method) expresses the circuit equations using differential equations and solves them simultaneously using finite difference technique. The results of the theoretical analysis is then compared to a commercial circuit simulation software program (Spectre ©) as well as to a low frequency hardware circuit utilizing discrete components. The presented analysis is shown to accurately model the high frequency simulation as well as the actual hardware circuit with the results discussed.
Library of Congress Subject Headings
Amplifiers (Electronics)--Design and construction; Integrated circuits
Klehn, Brett, "A Precise analysis of a class e amplifier" (2009). Thesis. Rochester Institute of Technology. Accessed from
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