Investigation of Logic Circuit Complexes: Universal Function Modules

摘要

The paper formulates and deals with some problems in universal function modules. A universal function module (UFM) is a variable logic structure capable of performing any function of n variables. The function performed by a UFM may be determined either by external switching or by a permutation of inputs, yielding fixed-connection and variable-connection UFMs, respectively. Among certain subclasses of these structures, optimal realizations are developed with respect to cost and reliability. Two new structures are discussed, one having active redundancy and correcting any single fault and the other possessing passive redundancy and correcting any two faults. Finally, the effect that passage of time has on redundant systems is considered, with special attention to triplication. It is shown that triplication and related reliability-increasing techniques actually decrease the expected time-to-failure of a system. (Author)