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:
Aug. 10, 1999
Filed:
Oct. 20, 1997
Ryosuke Fujio, Tokyo, JP;
Mitsuru Sekiguchi, Tokyo, JP;
NEC Corporation, Tokyo, JP;
Abstract
In a semiconductor memory device comprising a plurality of memory arrays, the memory array is given a predetermined potential from a terminal via a reference line. Further, a plurality of source switches are connected to the memory arrays and the reference line. The source switches selectively transfer the predetermined potential to each of the memory arrays. In this case, each of the source switches includes a transistor having an electrical ability which is determined by a length of the reference line between each source switch and the terminal. When the transistor is formed by a MOS transistor, the above electrical ability is specified by the ON resistance of the MOS transistor. The MOS transistors are designed so that the ON resistance becomes lower as the length of the reference line between the source switch and the terminal becomes longer. At any rate, a substantially constant voltage is supplied to each of the memory arrays irrelevant of the length of the reference line between each source switch and the terminal.