Partial bus-invert bus encoding schemes for low-power DSP systems considering inter-wire capacitance

Abstract

In this work, we develop simple yet very effective bus encoding schemes that dramatically reduce both self and coupling transition activity in common DSP signals. We show that, efficient low-power codes must cope with the different statistical characteristics of the most and least significant bits. On one hand, the high correlation in the most significant bits can be exploited by employing a simple non-redundant code. On the other hand, Bus Invert based codes are very efficient when applied only on the poorly correlated uniformly distributed least significant bits. The latter should not be employed on the most significant bits in order to preserve their high correlation. Additionally, we show that low-power codes can be easily compared by means of a simple graphical method. © Springer-Verlag Berlin Heidelberg 2006.