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:
Jul. 27, 2004
Filed:
May. 01, 2003
Kenichi Origasa, Takatsuki, JP;
Matsushita Electric Industrial Co., Ltd., Kadoma, JP;
Abstract
The present invention provides a semiconductor memory device whose circuit area is comparatively small and that improves holding characteristics of data in a memory cell. In a word line voltage generator, a voltage Vdd3 of a second power source that is higher than a voltage Vdd of a first power source supplied to the memory cell is applied to a first operational amplifier circuit and a reference voltage generating circuit, and the reference voltage generating circuit generates a voltage that is higher, by a voltage generated through a diode connection of a p-channel transistor, than the voltage proportional to the voltage Vdd as a first reference voltage Vref, and the first operational amplifier circuit outputs a voltage equal to the first reference voltage Vref as a word line drive voltage Vwl. Thus, a leakage current when the memory cell is off can be reduced, without requiring a charge pump circuit or the like.