A class D headphone amplifier with DC coupled outputs and 1.2mA quiescent current

Author

Huffenus, Alexandre ; Pillonnet, Gäel ; Abouchi, Nacer ; Taupin, Vincent Rabary Sophie ; Goutti, Frédéric

Author_Institution

CPE-INL, Univ. of Lyon, Villeurbanne, France

fYear

2011

fDate

26-29 June 2011

Firstpage

281

Lastpage

284

Abstract

This paper shows the design of a headphone amplifier using Pulse Width Modulation (PWM) to improve its power efficiency compared to existing Class AB and Class G structures. A numerical optimization of the switching frequency and output transistors size, combined with the use of a soft switching scheme, brought the current consumption down to 1.2mA at idle for the complete stereo amplifier. The outputs are DC coupled, with no common mode voltage, thanks to the use of a Negative Charge Pump (NCP). Theory of operation, optimization, and the design in a 0.25μm CMOS process will be explained.

Keywords

CMOS analogue integrated circuits; audio-frequency amplifiers; charge pump circuits; numerical analysis; optimisation; CMOS process; DC coupled outputs; PWM; class AB structures; class D headphone amplifier; class G structures; complete stereo amplifier; current 1.2 mA; negative charge pump; numerical optimization; pulsewidth modulation; size 0.25 mum; soft switching scheme; switching frequency;

fLanguage

English

Publisher

ieee

Conference_Titel

New Circuits and Systems Conference (NEWCAS), 2011 IEEE 9th International

Conference_Location

Bordeaux

Print_ISBN

978-1-61284-135-9

Type

conf

DOI

10.1109/NEWCAS.2011.5981310

Filename

5981310