A 85 /spl mu/W asynchronous filter-bank for a digital hearing aid

This asynchronous re-implementation of a 7-band interpolated FIR (IFIR) filter bank is part of the DigiFocus digital hearing aid manufactured by Oticon Inc. When processing typical data (less than 50 dB sound pressure), the power consumption of the asynchronous chip is 85 /spl mu/W-more than 5 times less than the existing synchronous design.