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. 12, 1994
Filed:
Dec. 23, 1992
Applicant:
Inventors:
Assignee:
NEC Corporation, Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H03K / ; H01L / ; G11C / ;
U.S. Cl.
CPC ...
3072961 ; 3072962 ; 3072966 ; 3073031 ; 3073032 ; 307304 ; 36518909 ; 365226 ;
Abstract
A dynamic random access memory device negatively biases the semiconductor substrate, and a substrate bias system incorporated therein produces a negative bias voltage from an external power voltage level for accelerating the negative biassing operation before an internal power voltage is sufficiently developed by an internal step-down circuit incorporated therein; however, after the development, the substrate bias system produces the negative bias voltage from the internal power voltage so as to be less affectable by fluctuation of the external power voltage level.