Technical Report Number
We investigate the impact of numerical representation on the power consumption of digital hearing aids. A fundamental building block, a non-linear ampliﬁer, is implemented using traditional 16-bit linear or customized 9-bit logarithmic and 10-bit ﬂoating point numerical representations. An individual channel of a multi-channel hearing aid is constructed, targeting both FPGA and ASIC deployment options. Using signal transition counts in the post-synthesis simulation to model power consumption, we compare the relative power consumption of the non-linear ampliﬁers, a full hearing aid channel, and the complete hearing aid signal processing for these three numerical representations. Our results show that for the non-linear ampliﬁer, the logarithmic and ﬂoating-point representations provide signiﬁcant savings over a traditional linear representation. However, since the total power consumption is dominated by the FIR ﬁlters, the total power saving is on the order of the ﬁlters.
Lu, Jing, "Power Consumption of Digital Hearing Aid Computations Using Customized Numerical Representations" Report Number: WUCSE-2003-35 (2003). All Computer Science and Engineering Research.