A 470μW clock-free current-controlled class D amplifier with 0.02% THD+N and 82dB PSRR

Author

Torres, Joselyn ; Colli-Menchi, Adrian ; Rojas-Gonzalez, Miguel Angel ; Sánchez-Sinencio, Edgar

Author_Institution

Dept. of Electr. & Comput. Eng., Texas A & M Univ., College Station, TX, USA

fYear

2010

fDate

14-16 Sept. 2010

Firstpage

326

Lastpage

329

Abstract

This paper presents a clock-free current-controlled class D audio power amplifier. The proposed audio amplifier is based on integral sliding mode control (ISMC) to ensure system robustness and to provide zero steady-state error. The proposed audio amplifier´s hysteretic controller obviates the traditionally challenging triangle-wave carrier signal design task for pulse-width modulation (PWM). The IC prototype consumes at least 30% less static power than previously reported works and delivers 250mW of output power with 84% efficiency. The class D amplifier achieves up to 82dB of power supply rejection ratio (PSRR), more than 95dB of signal-to-noise ratio (SNR) over the entire audio band, and 0.02% of total harmonic distortion plus noise (THD+N). The audio amplifier was fabricated in 0.5μm CMOS standard technology, operates at 380kHz, and occupies 1.65mm².

Keywords

audio-frequency amplifiers; power amplifiers; pulse width modulation; variable structure systems; audio power amplifier; clock-free current-controlled class D amplifier; integral sliding mode control; power 470 muW; pulse-width modulation; triangle-wave carrier signal; zero steady-state error; CMOS integrated circuits; Inductors; Modulation; Power generation; Power supplies; Resistors; Signal to noise ratio;

fLanguage

English

Publisher

ieee

Conference_Titel

ESSCIRC, 2010 Proceedings of the

Conference_Location

Seville

ISSN

1930-8833

Print_ISBN

978-1-4244-6662-7

Type

conf

DOI

10.1109/ESSCIRC.2010.5619709

Filename

5619709