The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 01, 1997
Filed:
Jun. 05, 1995
Genichiro Inoue, Osaka, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
The present invention discloses a multiplication device. A multiplicand X of eight bits and a multiplier Y of eight bits are input and a product P of sixteen bits is found from these multiplication factors. MULTIPLICAND X is divided into two parts, an upper-order part X.sub.U of four bits and a low-order part X.sub.L of four bits. MULTIPLIER Y is likewise divided into two parts, an upper-order part Y.sub.U of four bits and a low-order part Y.sub.L of four bits. Thereafter, four 8-bit partial products, i.e., X.sub.L .times.Y.sub.L, X.sub.L .times.Y.sub.U, X.sub.U .times.Y.sub.L, and X.sub.U .times.Y.sub.U are computed one after another. These partial products are subjected to a digit place alignment addition operation, by an adder, to compute PRODUCT P. Computation of each of the partial products is implemented by performing addition of an approximate partial product AP retrieved by a 6-bit address from a 64-byte ROM, and a correction value H and a carry C generated by a correction value generator.