Filterless Multi-level Delta-sigma Class-D Amplifier for Portable Applications. - Atsushi Matamura; Naoaki Nishimura; Bill Yang Liu (ISCAS, 2009)

31.1 An 82mW ΔΣ - Based Filter-Less Class-D Headphone Amplifier with -93dB THD+N, 113dB SNR and 93% Efficiency. - Atsushi Matamura; Naoaki Nishimura; Preston Birdsong; Abhishek Bandyopadhyay; Adam Spirer; Mariana T. Markova; Shaolong Liu (ISSCC, 2021)

An 82-mW ΔΣ-Based Filter-Less Class-D Headphone Amplifier With -93-dB THD+N, 113-dB SNR, and 93% Efficiency. - Atsushi Matamura; Naoaki Nishimura; Preston Birdsong; Abhishek Bandyopadhyay; Adam Spirer; Mariana T. Markova; Shaolong Liu (IEEE J. Solid State Circuits, 2021)

Common-mode Stable Multilevel Output Stage with EMI Reduction Feedback Loop for Class-D audio Amplifier. - Naoaki Nishimura; Atsushi Matamura; Preston Birdsong; Shaolong Liu; Abhishek Bandyopadhyay; Mariana T. Markova; Rajeev Morajkar (VLSI Technology and Circuits, 2022)