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:
Jun. 29, 2010
Filed:
Nov. 30, 2007
Yasuyuki Eguchi, Kawasaki, JP;
Shinya Fujioka, Kawasaki, JP;
Yoshiaki Okuyama, Kirishima, JP;
Fujitsu Semiconductor Limited, Yokohama, JP;
Abstract
A refresh register stores disable block information indicating a memory block whose refresh operation is to be disabled. A refresh control circuit periodically executes the refresh operation of a memory block except the memory block corresponding to the disable block information. During an access cycle to one of the memory blocks, the register control circuit writes the disable block information to the refresh register according to an external input. Consequently, in order to rewrite the refresh register, it is not necessary to use an additional operation cycle to the access cycle. Since there is no need to insert an extra operation cycle, it is possible to change a memory area to be refreshed without lowering effective efficiency of access cycles. As a result, power consumption can be reduced.