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:
Sep. 15, 1987
Filed:
Mar. 06, 1985
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
A semiconductor memory device comprises a plurality of row decoder circuits connected with word lines for selecting memory cells. The row decoder circuits include normal row decoder circuits and spare row decoder circuits which can be selected in place of a normal row decoder circuit in case where a fault occurs in a memory cell selected by a word line connected to the normal row decoder circuit. An RAS signal (precharge signal) is applied to an output line (12) of a normal row decoder circuit through a precharge bus (31). A link element (11p) is inserted in the precharge bus (31). The link element (11p) is an element which can be melted by a laser beam, whereby the normal row decoder circuit associated is maintained in a non-selective state. A clamp circuit (14) is also connected to the output line (12). The clamp circuit (14) is a circuit for maintaining the output line (12) at a prescribed low level when the link element (11p) is melted and the associated decoder circuit is brought into a non-selective state.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile