Modular Replacement of Combinational Switching Networls

This paper discusses a technique whereby a logic design which is unconstrained may be replaced quasi-optimally with modules from a constrained library. Necessary and sufficient conditions for the replacement of modules within a network are developed and then reformulated as integer linear programs. These integer linear programs are solved during individual steps of a dynamic programming formulation of the network replacement problem. Execution time of the algorithm increases linearly with the network size and the algorithm produces optimal replacements of fan-out-free networks.