Design and performance analysis of class-B power amplifier with double-gate MOSFET.

Abstract

This work presents the design of a class-B power amplifier with the use of Double-Gate (DG) Metal-Oxide-Semiconductor Field-Effect Transistor (MOSFET). It analyzes the indices of system performance indices for class-B power amplifiers using DG MOSFET. It presents a comparative analysis of three power amplifiers using different switching devices, i.e., BJT, traditional single-gate MOSFET, and designed amplifier using DG MOSFET. It was realized that the class-B power amplifier with the use of DG MOSFET reduces the crossover distortion which is a major issue faced by class-B power amplifiers. The hardware design is also presented and tested with advanced electronic components such as oscilloscope, function generator, and DC power supply, it was observed that the crossover distortions are not exist in the output waveforms of the hardware circuit design. The class-B power amplifier is commonly used for power amplification due to its performance, such as high input signal fidelity at the output and high-power efficiency. These power amplifiers are being designed and simulated to test the switching speed to receive the output signal when an input signal is applied. The comparison of these three power amplifier circuits is taken to conclude which power amplifier circuit performs better regarding its switching speed. The basics switching speed is the time the power takes to amplify the signal, which is the same as the time to amplify the signal to a specific gain. In addition, the settling time for these three types of power amplifiers also have been tested and presented to justify the performance of these three types of power amplifiers. Losses of the class-B power amplifier using DG MOSFET are presented and compared to the design of class-B power amplifier using traditional single-gate MOSFET. This thesis describes the design of a power amplifier having DG MOSFET, which is a device used to amplify any input signal; it can be an audio signal or any signal. The thesis provides information on the problem identification/description, design objectives/requirements, and the design specifications, both functional and non-functional, together with design constraints and simulation circuits. Various solutions to the problem are discussed and the preferred solution is proposed, together with analysis.