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:
Mar. 06, 2007
Filed:
Dec. 02, 2005
Masato Takita, Kawasaki, JP;
Masato Takita, Kawasaki, JP;
Fujitsu Limited, Kawasaki, JP;
Abstract
A shift register includes plural latches corresponding to normal word lines of normal memory cell rows and a redundancy word line of a redundancy memory cell row, respectively, in order to sequentially activate any of the redundancy word line and the normal word lines upon every refresh request. An activation circuit activates any of the normal word lines and redundancy word line according to an output of the shift register. A first storing circuit stores in advance a defect address indicating a defective normal memory cell row. A first activation control circuit prohibits activation of a normal word line corresponding to the defect address stored in the first storing circuit when the output of the shift register indicates the normal word line.