Universal Logic Modules and Their Applications

Recent advances in integrated circuit technology and its potential advantage in logical design have motivated the search for modular synthesis techniques for logic networks. This problem may be divided into two parts: find appropriate modules; and develop efficient synthesis techniques for logic networks using a minimum number of modules. In this paper a new type of universal logic modules (ULM's) called the Q-type is presented. The Q-type ULM's are superior to the existing ULM's in the sense that they require fewer input/output terminals when n≥6 where n is the number of input variables of the ULM. Various techniques for synthesizing a logic network with a small number of ULM's are discussed. A much simpler type of modules, which is suitable to realize any symmetric or partially symmetric function and can be used as auxiliary building blocks for realizing any given logic function, is presented. A special kind of ULM's, called serially controlled ULM's which has only n+3 input/output terminals, is also presented. For a ULM of this kind the signals for specifying the logic function to be realized are serially applied to one of its input terminals.