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. 02, 1990
Filed:
Oct. 31, 1989
Shuuichi Miyaoka, Ohme, JP;
Masanori Odaka, Kodaira, JP;
Hiroshi Higuchi, Ohme, JP;
Toshikazu Arai, Ohme, JP;
Hitachi, Ltd., Tokyo, JP;
Hitachi Microcomputer Engineering, Tokyo, JP;
Akita Electronics, Co., Ltd., Akita, JP;
Abstract
A semiconductor memory device is provided which includes a plurality of memory arrays each including main word lines, sub word lines to which a plurality of memory cells are connected, and a decoder which selectively connects the sub word lines to the main word lines. The main word lines are relatively short, since they are isolated electrically between memory arrays, and their resistance can thus be relatively low. The main word lines are not directly connected with a plurality of memory cells, and this results in a smaller capacitance coupled to the main word lines than is customarily the case. Consequently, the semiconductor memory device can have an enhanced operating speed.