A 16-channel low-power non-uniform spaced filter bank core for digital hearing aids

Abstract

We describe a 16-channel critical-like spaced, high stopband attenuation (≥60 dB, 109th X 16-order), micropower (247.5 W@1.1 V, 0.96 MHz), small integrated circuit (IC) area (1.62 mm2@0.35- m CMOS) finite impulse response filter bank core for power-critical hearing aids. We achieve the low-power

and small IC area attributes by our proposed common pre-computational unit to generate a set of pre-calculated intermediate

values that is shared by all 16 channels. We also take advantage of the consecutive zeros in the coefficients of the filter channels, allowing the multiplexers therein to be simplified. We show that our design is very competitive compared to reported designs, and with the advantages of higher stopband attenuation and linear phase frequency response. Compared to a design using the usual approach, our design features 47% lower power dissipation and 37% smaller IC area.