Adaptive signal to noise ratio scalable analog front-end continuous time sigma delta converter for digital hearing aids
Description
A dual-channel directional digital hearing aid (DHA) front end using Micro Electro Mechanical System (MEMS) microphones and an adaptive-power analog processing signal chain is presented. The analog front end consists of a double differential amplifier (DDA) based capacitance to voltage conversion circuit, 40dB variable gain amplifier (VGA) and a continuous time sigma delta analog to digital converter (CT - ΣΔ ADC). Adaptive power scaling of the 4th order CT - ΣΔ achieves 68dB SNR at 120μW, which can be scaled down to 61dB SNR at 67μW. This power saving will increse the battery life of the DHA.
Date Created
The date the item was original created (prior to any relationship with the ASU Digital Repositories.)
2010
Agent
- Author (aut): Deligoz, Ilker
- Thesis advisor (ths): Kiaei, Sayfe
- Committee member: Bakkaloglu, Bertan
- Committee member: Jalali-Farahani, Bahar
- Committee member: Aberle, James T., 1961-
- Committee member: Chae, Junseok
- Publisher (pbl): Arizona State University