Partial bus-invert coding for power optimization of application-specific systems

This paper presents two bus coding schemes for power optimization of applic ation-specific systems: Partial Bus-invert coding and its extension to Mult iway Partial Bus-invert coding. In the first scheme, only a selected subgro up of bus lines is encoded to avoid unnecessary inversion of relatively ina ctive and/or uncorrelated bus lines which are not included in the subgroup. In the extended scheme, we partition a bus into multiple subbuses by clust ering highly correlated bus lines and then encode each subbus independently . We describe a heuristic algorithm of partitioning a bus into subbuses for each encoding scheme. Experimental results for various examples indicate t hat both encoding schemes are highly efficient for application-specific sys tems.