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:
Jul. 25, 1989
Filed:
Aug. 13, 1987
Hiromichi Aoki, Tokyo, JP;
NEC Corporation, , JP;
Abstract
In an arithmetic unit comprising a partial product circuit for calculating a plurality of partial products for two numbers and a Wallace tree responsive to the partial products for producing a plurality of tree outputs which gives a total product of the two numbers when summed up, an addend is supplied to the Wallace tree as an additional partial product. The arithmetic unit produces a resultant sum of the total product plus the addend. The addend may be supplied to the Wallace tree from one or more registers therefor. Alternatively, a result register is used for the total product with the total product supplied to the Wallace tree as the addend. As a further alternative, an additional register is used for a third number which is used with bit shifts as the addend. In this last event, the arithmetic unit preferably produces a sum selected from the resultant sum.