This paper proposes split shared-bus architecture to reduce the energy dissipation for global data exchange among a set of interconnected modules. The bus splitting problem for minimum energy is formulated as a Minimum-Exchange Bus Split problem, which is shown to be NP-complete. The problem is solved heuristically by using a max-weight matching algorithm and combinatorial search. Experimental results show that the energy saving of split-bus architecture compared to monolithic-bus architecture varies from 16% to 50%, depending on the characteristics of the data transfer among the modules and the configuration of the split-bus. The proposed split-bus architecture can be extended to multi-way split-bus architecture when large numbers of modules are to be connected.