Abstract—An electronic hearing aid is a small device which is located in and around the human ear to enhance the hearing ability. It is used to compensate the hearing loss and enhance the quality of sound for hearing impaired people. Hearing aid device in signal processing is an important field of research for the last three decades. Recently, power aware hearing aid device designs with smaller footprint, gain considerable importance. The hearing aid device has been designed for portable communication equipment with digital filtering, speech processing, sub-band coding and speech enhancement. With the technological advancements in the Digital Signal Processing (DSP) algorithms, design of hearing aid devices has been improved continuously. It is expected that more innovations in hearing aid device technology will be released in future, with new developments in signal processing algorithms and filter bank designs. Finite Impulse Response (FIR) filter design is very important and crucial for signal processing algorithms. The focus of the designer is on minimization of power on the domain of digital circuit for battery operated devices. In this paper, Gated Diffusion Input (GDI) logic is used in the proposed Filter Bank design in order to minimize power. The Multiply-Accumulate (MAC) unit of the proposed filter bank is designed by GDI logic and modified GDI logic. GDI logic has three terminals which are Common Gate (G), PMOS (P), NMOS (N) and output terminal. The number of transistors is reduced in GDI when compared to Complementary Metal Oxide Semiconductor (CMOS) logic due to reduced switching activity. This paper briefly describes the basic functions of power and delay of GDI logic and modified GDI logic. The proposed modified GDI logic provides better results in area and power when compared to CMOS logic.

 

Index Terms—filter bank, digital hearing aid, DSP algorithms, multiply accumulate unit

Cite: N. Subbulakshmi and R. Manimegalai, "MACGDI: Low Power MAC Based Filter Bank Using GDI Logic for Hearing Aid Applications," International Journal of Electronics and Electrical Engineering, Vol. 5, No. 3, pp. 235-239, June 2017. doi: 10.18178/ijeee.5.3.235-239