A Class-AB/D Audio Power Amplifier for Mobile Applications Integrated Into a 2.5G/3G Baseband Processor

Author

Groeneweg, Willem H. ; Pilloud, Bernard ; Neri, Filippo ; Notermans, Guido ; Balucani, Marco ; Helfenstein, Markus

Author_Institution

Cellular Syst. & Connectivity Div., ST-Ericsson, Zurich, Switzerland

Volume

57

Issue

5

fYear

2010

fDate

5/1/2010 12:00:00 AM

Firstpage

1003

Lastpage

1016

Abstract

A filterless class-AB/D audio power amplifier integrated into a feature-rich 2.5G/3G baseband processor in standard 65-nm CMOS technology is designed for direct battery hookup in mobile phone applications. Circuit techniques are used to overcome the voltage limitations of standard MOS transistors for operation at voltage levels of 2.5-4.8 V. Both amplifiers can drive more than 650 mW into an 8-?? load with maximum distortion levels of 1% and 5% for class-D and class-AB, respectively, all from a 3.6-V power supply. The achieved power-supply-rejection ratios are 72 and 84 dB, respectively. The mono implementation of both amplifiers together is 0.44 mm² .

Keywords

CMOS analogue integrated circuits; audio-frequency amplifiers; microprocessor chips; mobile handsets; power amplifiers; 2.5G baseband processor; 3G baseband processor; CMOS technology; D audio power amplifier; MOS transistors; circuit techniques; class-AB audio power amplifier; maximum distortion levels; mobile phone; power-supply-rejection ratios; resistance 8 ohm; size 65 nm; voltage 2.5 V to 4.8 V; Baseband processor; CMOS; SoC; class-AB amplifier; class-D amplifier; system-on-chip;

fLanguage

English

Journal_Title

Circuits and Systems I: Regular Papers, IEEE Transactions on

Publisher

ieee

ISSN

1549-8328

Type

jour

DOI

10.1109/TCSI.2010.2046954

Filename

5460955