A MEMS-Based Power-Scalable Hearing Aid Analog Front End

Author

Deligoz, I. ; Naqvi, S.R. ; Copani, T. ; Kiaei, S. ; Bakkaloglu, B. ; Sang-Soo Je ; Junseok Chae

Author_Institution

Electr., Comput. & Energy Eng. Dept., Arizona State Univ., Tempe, AZ, USA

Volume

5

Issue

3

fYear

2011

fDate

6/1/2011 12:00:00 AM

Firstpage

201

Lastpage

213

Abstract

A dual-channel directional digital hearing aid front end using microelectromechanical-systems microphones, and an adaptive-power analog processing signal chain are presented. The analog front end consists of a double differential amplifier-based capacitance-to-voltage conversion circuit, 40-dB variable gain amplifier (VGA) and a power-scalable continuous time sigma delta analog-to-digital converter (ADC), with 68-dB signal-to-noise ratio dissipating 67 μ W from a 1.2-V supply. The MEMS microphones are fabricated using a standard surface micromachining technology. The VGA and power-scalable ADC are fabricated on a 0.25-μ m complementary metal-oxide semciconductor TSMC process.

Keywords

CMOS integrated circuits; acoustic signal processing; amplifiers; analogue circuits; biomedical electronics; hearing aids; low-power electronics; medical signal processing; micromachining; micromechanical devices; microphones; power supplies to apparatus; sigma-delta modulation; CMOS TSMC process; MEMS based hearing aid analog front end; MEMS microphones; VGA; adaptive power analog processing signal chain; analog-digital converter; capacitance-voltage conversion circuit; double differential amplifier; dual channel directional digital hearing aid front end; gain 40 dB; microelectromechanical systems; power 67 muW; power scalable ADC; power scalable continuous time sigma-delta ADC; power scalable hearing aid analog front end; signal-noise ratio; surface micromachining technology; variable gain amplifier; voltage 1.2 V; Acoustics; Auditory system; Capacitance; Gain; Micromechanical devices; Microphones; Noise; Continuous time sigma-delta modulation; digital hearing aids; directional microphone array; microelectromechanical-systems (MEMS) microphone;

fLanguage

English

Journal_Title

Biomedical Circuits and Systems, IEEE Transactions on

Publisher

ieee

ISSN

1932-4545

Type

jour

DOI

10.1109/TBCAS.2010.2079329

Filename

5611627