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. 11, 2005
Filed:
Aug. 05, 2003
Kouichiro Ninomiya, Kodaira, JP;
Isamu Fujii, Kodaira, JP;
Hiroki Fujisawa, Tokyo, JP;
Elpida Memory, Inc., Tokyo, JP;
Hitachi ULSI Systems Co., Ltd., Tokyo, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A semiconductor memory device is capable of performing a faster operation by reducing a load applied to a subword selection line or driving a subword driver provided for each memory mat. In a drive method of subword drivers that are actuated in response to subword selection signals supplied through subword selection lines, the subword selection lines are branched according to the number of memory mats. Each subword selection signal has a polarity to a branching position and an inverted polarity from each branching position to each subword driver. The inverted subword selection signal together with a main word signal are calculated to operation in each subword driver and output as a subword drive signal. The plurality of subword drivers share an inverter circuit for inverting the main word signals so as to permit a simplified circuit configuration.