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:
Jun. 13, 1995
Filed:
Apr. 08, 1993
Fuyuki Okamoto, Tokyo, JP;
NEC Corporation, Tokyo, JP;
Abstract
A priority encoder for a normalization at a floating-point addition of subtraction for encoding a leading zero number of a difference of two input binary numbers within an error of -1, and a floating-point adder-subtractor using this priority encoder. The priority encoder includes a pre-encoder for outputting an n-bit bit string Q (=Q.sub.n, Q.sub.n-1, . . . and Q.sub.1,) from a combination (X.sub.i, Y.sub.i, X.sub.i-1, Y.sub.i-1) of ith and (i-1)th digits of input two binary numbers X and Y, and a conventional priority encoder circuit for encoding the bit string Q output from the pre-encoder. The floating-point adder-subtractor includes the priority encoder operating in parallel with a mantissa add-subtract circuit so as to output the leading zero number of the difference between the two binary numbers X and Y.