2026-05-22T08:42:28Zhttps://keep.lib.asu.edu/oai/requestoai:keep.lib.asu.edu:node-1502082024-12-20T18:25:12Zoai_pmh:alloai_pmh:repo_items150208
https://hdl.handle.net/2286/R.I.9517
http://rightsstatements.org/vocab/InC/1.0/
All Rights Reserved
2011
ix, 97 p. : ill. (some col.)
Doctoral Dissertation
Academic theses
Text
eng
Lee, Junghan
Bakkaloglu, Bertan
Kiaei, Sayfe
Ozev, Sule
Song, Hongjiang
Arizona State University
Partial requirement for: Ph.D., Arizona State University, 2011
Includes bibliographical references (p. 93-97)
Field of study: Electrical engineering
Pulse Density Modulation- (PDM-) based class-D amplifiers can reduce non-linearity and tonal content due to carrier signal in Pulse Width Modulation - (PWM-) based amplifiers. However, their low-voltage analog implementations also require a linear- loop filter and a quantizer. A PDM-based class-D audio amplifier using a frequency-domain quantization is presented in this paper. The digital-intensive frequency domain approach achieves high linearity under low-supply regimes. An analog comparator and a single-bit quantizer are replaced with a Current-Controlled Oscillator- (ICO-) based frequency discriminator. By using the ICO as a phase integrator, a third-order noise shaping is achieved using only two analog integrators. A single-loop, singlebit class-D audio amplifier is presented with an H-bridge switching power stage, which is designed and fabricated on a 0.18 um CMOS process, with 6 layers of metal achieving a total harmonic distortion plus noise (THD+N) of 0.065% and a peak power efficiency of 80% while driving a 4-ohms loudspeaker load. The amplifier can deliver the output power of 280 mW.
Electrical Engineering
Engineering
Class-D amplifier
Current-Controlled Oscillator
Frequency discriminators
Frequency-domain Quantization
Pulse Density Modulation
Sigma-Delta Modulation
Audio amplifiers
Voltage-controlled oscillators
Pulse-duration modulation
A 280 mW, 0.07 % THD+N class-D audio amplifier using a frequency-domain quantizer