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:
Jan. 29, 2013
Filed:
Jul. 20, 2010
Tomonori Hayashi, Tokyo, JP;
Akihiko Kagami, Tokyo, JP;
Yuji Sugiyama, Tokyo, JP;
Elpida Memory, Inc., Tokyo, JP;
Abstract
A semiconductor memory device includes a mask information storage circuit that stores therein mask information indicating an area for which the self refresh operation is not performed among a plurality of areas in a memory cell array, a mask determining circuit that is activated by a self refresh command and generates a match signal in response to a detection of a match between a refresh address and the mask information, and a refresh operation control circuit that disables the self refresh operation in response to an activation of the match signal. When a test mode signal is activated, the mask determining circuit is also activated by the auto refresh command. With this configuration, it is possible to perform a test of a partial array self refresh function without actually entering a self refresh mode.