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:
Mar. 30, 2004
Filed:
Jan. 23, 2003
Hiroyuki Takahashi, Tokyo, JP;
Masatoshi Sonoda, Tokyo, JP;
NEC Electronics Corporation, Kanagawa, JP;
Abstract
The present invention provides a semiconductor memory device and control method capable of effectively suppressing the generation of operating current originating in noise of address signals provided from the outside without impairing the operating speed during reading and writing. This semiconductor memory device is provided with a filter circuit ( ) for removing noise contained in address signals provided from the outside, a circuit system containing an ATD circuit ( ) for generating a first address transition detection signal (&phgr;ATD ) by detecting a change in an address signal prior to passing through the filter circuit ( ), and a circuit system containing an ATD circuit ( ) for generating a second address transition detection signal (&phgr;ATD ) by detecting a change in an address signal after passing through the filter circuit ( ). Refresh operation is controlled by first address transition detection signal (&phgr;ATD ), while read/write operation is controlled by second address transition detection signal (&phgr;ATD ). As a result, only the refresh operation is performed in the case noise has been generated, and the generation of operating current is effectively suppressed.