Interlaced programmable logic array having shared elements

摘要

A programmable PLA circuit in which an interlaced AND/OR array is provided which has both common input and common output lines. Separate AND and OR functions are generated during two different timing intervals such that both of the logical arrays can physically share input and output circuit elements. A binary adder is described in which pairs of array output lines are applied to the same Exclusive-NOR circuits during the two time intervals to provide the Exclusive-NOR of product terms during the AND array time interval and to provide the Exclusive-NOR of sum of product terms or the sum of the Exclusive-NOR of product terms during the second time interval.