Logic gate size optimization process for an integrated circuit whereby

Abstract

An integrated circuit, when designed, must adhere to timing constraints while attempting to minimize circuit area. In order to adhere to timing specifications while arriving at a near-optimal circuit surface area, an iterative process is used which selectively increases logic gates sizes by accessing logic gates from a memory stored logic gate library. A circuit representation is read along with timing constraints for circuit paths. Each circuit path in the circuit is processed to find it's actual circuit path delay. A most out-of-specification circuit path (in terms of speed) is chosen in the circuit and a sensitivity calculation is performed for each logic gate in the most out-of-specification circuit path. The logic gate in the circuit path with the maximized sensitivity (sensitivity=.DELTA.speed/.DELTA.area) is increased in size by accessing a larger gate in the library in order to improve speed at the expense of area. The above process continues iteratively until no out-of-specification circuit paths are found.