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:
May. 07, 1996
Filed:
Nov. 09, 1994
Atul V Ghia, San Jose, CA (US);
Pradip Banerjee, San Jose, CA (US);
Patrick Chuang, Cupertino, CA (US);
Sony Corporation of Japan, , US;
Sony Electronics, Inc., Park Ridge, NJ (US);
Abstract
The present invention discloses apparatus and methods for comparing the contents of two digital words and determining whether or not they identically match. The present invention's high speed compare circuit includes a plurality of bit compare block circuits (0 through N) which are coupled in a wired OR configuration to a match line. Each of the bit compare blocks receives a single bit from a first word A to be compared to a corresponding bit in a second word B. A charge share precharge circuit is coupled to the match line for precharging the match line to a voltage level of V.sub.cc /2. A match feed back circuit is also coupled to the match line and the charge precharge circuit to improve the speed at which the match line is precharged to the voltage level of V.sub.cc /2. A latch is coupled to the match line to electrically latch the state of the match line subsequent to the comparison operation. The comparison circuit of the present invention is dynamic and retains its high speed performance characteristics independent of the word lengths being compared.