Decomposition of Boolean Functions Specified by Cubes:
Part II: Practical Results

M. Nowicka and T. Luba
Institute of Telecommunications
Warsaw Institute of Technology
Nowowiejska 15/19
00-665 Warsaw, Poland

We describe DEMAIN - a program for the decomposition of multiple-output, incompletely specified, Boolean functions represented in the consistent-cube notation (fr format). We compare the results of DEMAIN with those of other tools, and show that, in most cases, DEMAIN produces better results on standard benchmark circuits and other designs. DEMAIN uses parallel, disjoint serial, and nondisjoint serial decompositions as steps in an iterative algorithm. Heuristic strategies are used to decide which type of decomposition should be used at a given step. This permits us to minimize either the area (number of cells) od delay (number of levels).

Keywords: decomposition, disjoint, FPGA, look-up table, nondisjoint, parallel, serial, strategies