Class D Amplifiers (CDAs) : PWM-in-PWM-out CDA, Filterless Bang-Bang CDA, and high-frequency high-efficiency CDA for Envelope Tracking

• Main Author: Kang, Yang
• Other Authors: Chang Joseph Sylvester
• Format: Thesis-Doctor of Philosophy
• Language: English
• Published: Nanyang Technological University 2020
• Subjects: Engineering::Electrical and electronic engineering::Integrated circuits
• Online Access: https://hdl.handle.net/10356/136586
• Institution: Nanyang Technological University

This Ph.D. program pertains to investigations into the mechanisms and parameters affecting the non-idealities and power-efficiency of Class D Amplifiers (CDAs), and our ensuing novel circuit designs (and proposal of novel architectures) to mitigate the aforesaid. There are three specific CDA architectures. The first is the PWM-In PWM-Out (PIPO) CDA, an emerging CDA whose input is PWM, hence highly compatible with digital signal processing. Our effort pertains to addressing its relatively high inherent non-linearities. The second is the Bang-Bang CDA, arguably the simplest CDA architecture, hence the CDA with the lowest hardware, and potentially the most power-efficient CDA. Our effort pertains to the design of a 3-state Bang-Bang CDA – to our knowledge the first 3-state (filterless) Bang-Bang CDA reported in literature – where we ascertain its fidelity and power-efficiency. The third is the high-frequency high-efficient CDA for the supply modulator of the Envelop Tracking (ET) Power Amplifier (PA) which serves as the power supply to a radio frequency (RF) PA. Our effort pertains to addressing the power-efficiency of the wideband PA.