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:
Nov. 09, 1999
Filed:
Sep. 26, 1997
Masashi Horiguchi, Kawasaki, JP;
Shinichi Miyatake, Hamura, JP;
Tathunori Mushya, Fussa, JP;
Yasuhiro Kasama, Musashino, JP;
Yoichi Matsuno, Kokubunji, JP;
Yasushi Kawase, Kokubunji, JP;
Yoshinobu Nakagome, Hamura, JP;
Hitachi, Ltd., Tokyo, JP;
Hitachi Ulsi Engineering Corp., Tokyo, JP;
Hitachi Device Engineering Co., Ltd., Mobara, JP;
Abstract
A semiconductor memory having a redundancy circuit includes a judgment device for receiving outputs of first ROMs for storing a defective address therein and judging whether or not a defective memory cell and a spare memory cell to replace the defective memory cell belong to the same memory cell, and also includes a timing adjustment circuit for changing the timing of control signals applied to memory mat control circuits according to an output of the judgment device. When the defective and spare memory cells belong to the same memory mat, the timing of the control signals is made fast.