Accession Number : AD0696056

Title :   UNIVERSAL LOGIC BLOCKS.

Descriptive Note : Interim rept.,

Corporate Author : NAVAL RESEARCH LAB WASHINGTON D C

Personal Author(s) : Shay,Barry P.

Report Date : 17 SEP 1969

Pagination or Media Count : 22

Abstract : Combinatorial networks are usually synthesized from integrated-circuit building blocks. Advances in integrated-circuit processing technology permit the placement of more logic on a single block, but raise two new questions as to what logical functions should be placed on a block and how combinatorial networks can be efficiently synthesized from a family of blocks. The Universal Logic Block (ULB) provides a promising approach towards answering these questions. A ULB produces a particular function of n Boolean variables (and its complement) that has the property of covering any Boolean function of k or fewer variables by suitable input partitioning. Such functions are known as Globally Universal (GU) functions. Currently available methods of finding GU functions depend upon realizing certain equivalence classes of Boolean functions. The enormous growth rate of these classes limits the practicality of such methods. Techniques must be found which either avoid the realization of equivalence classes, or enlarge each class by defining new relations on the set of Boolean functions. The synthesis of large networks using the GU block as the logical connective remains a difficult problem. By placing constraints on the desired network, realistic design criteria can be established. Considerations to be taken into account include size of the block to be used, delays associated with the block, and the mixing of various types of blocks. (Author)

Descriptors :   (*LOGIC CIRCUITS, *INTEGRATED CIRCUITS), COMPUTER LOGIC, SYNTHESIS, OPTIMIZATION, MODULES(ELECTRONICS), MATHEMATICAL LOGIC, ALGEBRAS

Subject Categories : Electrical and Electronic Equipment

Distribution Statement : APPROVED FOR PUBLIC RELEASE