ETAM++: extended transition activity measure for low power address bus designs

Interconnection networks in Systems-On-Chip (SoC) begin to have a non-negligible impact on the power consumption of a whole system. This is because of increasing inter-wire capacitances that are in the same order of magnitude as intrinsic capacitances as far as deep-submicron designs are concerned. This trend has been recognized in recent research work. In this work, we present a physical model that takes into account inter-wire capacitances. Subsequently we propose a novel encoding scheme based on this physical model and targeted for address buses. We demonstrate that our encoding method improves power consumption by up to 62.5% and thus is exceeding all current approaches including our own previous one. In addition, the hardware of the bus encoding/decoding interfaces is compact to implement. We have conducted extensive simulations using SoC applications like, for example, an MPEGII encoder to evaluate the advantages of our approach.