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:
Oct. 25, 1994
Filed:
Apr. 23, 1992
Shigetoshi Sakomura, Ohme, JP;
Kazuya Ito, Hamura, JP;
Hidetoshi Iwai, Ohme, JP;
Toshiyuki Sakuta, Ohme, JP;
Masamichi Ishihara, Hamura, JP;
Tomoshi Matsumoto, deceased, late of Kochi, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A semiconductor memory device is provided which includes a plurality of data lines, at least one redundant data line, one common data line, a plurality of column switches installed between the plurality of data lines and the redundant data line and one common data line, and a column decoder for controlling the plurality of column switches. The column decoder operates to turn the column switch on. The column switch is connected to a plurality of data lines, excluding any defective data and redundant data lines during the test mode state.