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:
Jun. 30, 2009
Filed:
Aug. 29, 2007
Mitsuaki Hayashi, Kyoto, JP;
Mitsuaki Hayashi, Kyoto, JP;
Panasonic Corporation, Osaka, JP;
Abstract
A semiconductor memory cell is implemented in which the area of a row selection circuit is reduced and the effects of exposure, etching, and so on performed during manufacture are eliminated. The semiconductor memory device is provided with word line selection circuits connected with a row address signal line to select some desired word line according to an address input and dummy word line potential fixation circuits connected to word lines for dummy memory cells. As in the case of the word line selection circuits, the dummy word line potential fixation circuits each include a NAND gate NANDR(i) (i=−1, 0, m+1, or m+2) and an inverter INVR(i) (i=−1, 0, m+1, or m+2). The inputs of the dummy word line potential fixation circuits are connected with a row address signal line such that the word lines for the dummy memory cells are maintained in a non-selected state at all times. These make it possible to make the circuits which selectively drive all the word lines identical with each other in configuration, reduce the area of the row selection circuit, and eliminate the effects of exposure, etching, and so on during manufacture.