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:
Sep. 21, 2004
Filed:
Oct. 01, 2002
Masami Nakashima, Kasugai, JP;
Mitsuhiro Higashiho, Beppu, JP;
Fujitsu Limited, Kawasaki, JP;
Abstract
There are provided a semiconductor memory device and a refresh control method thereof to realize a refresh operation without any problem for external accesses while realizing low current dissipation operations for executing the refresh operation in separation from external access operation, in which the refresh operation is inhibited during execution of the external accesses. During this period, the internal operation in the refresh operation is controlled for the first refresh-operation-start request, but the internal operation for the second and subsequent refresh operation start requests is inhibited. Even when a plurality of refresh-operation-start requests are outputted previously while the refresh operation is inhibited during the external access operation, only the internal operation is not executed previously and the refresh operations after completion of the external access operation can surely be executed.