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. 07, 2003
Filed:
May. 01, 2002
Applicant:
Inventor:
Kyoji Yamasaki, Hyogo, JP;
Assignee:
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G11C 7/00 ;
U.S. Cl.
CPC ...
G11C 7/00 ;
Abstract
The DRAM includes a power supply switching circuit which provides a word line select circuit with a power supply potential when a test signal is activated. The potential of a main word line becomes an H level equal to the power supply potential when a word line is not selected. Thus, when a sub-decode signal attains an H level equal to a boosted potential, not only an N channel MOS transistor but also a P channel MOS transistor turn on in a word line driver, and a leakage current running through the word line driver comes to flow. Accordingly, large stress is imposed on the P channel MOS transistor.