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:
Feb. 02, 1999
Filed:
Oct. 17, 1995
Applicant:
Inventor:
Hsueh-Li Joseph Yeh, Cupertino, CA (US);
Assignee:
Hitachi Micro Systems, Inc., San Jose, CA (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G06F / ;
U.S. Cl.
CPC ...
36474807 ; 36474811 ;
Abstract
A fast floating-point multiplication and accumulation unit (fmac) is described. The described fmac uses significantly less hardware, thereby yielding a fast and an inexpensive fmac. This fmac uses an m-bit carry propagation adder instead of a 3 m-bit carry propagation adder and a 2 m-bit normalizer instead of a 3 m-bit normalizer. The normalizer relies on a leading one detection, as opposed to leading one/zero prediction used in known fmac's. Even when the product of the multiplication is opposite in sign to the number added to the product, the fmac, disclosed here, only uses an m-bit adder and a 2 m-bit normalizer.