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:
Apr. 10, 2007
Filed:
Nov. 03, 2005
Satoshi Eto, Kawasaki, JP;
Satoshi Eto, Kawasaki, JP;
Fujitsu Limited, Kawasaki, JP;
Abstract
A data additional circuit adds plural types of expectation data to be read from a refresh block to data read from other blocks, respectively, to generate plural read data strings. An error correction circuit detects errors for each read data string, and sets the most reliable result of the error detection results to be true. The error correction circuit decodes data to be read from the refresh block based on a true error detection result. Moreover, the error correction circuit corrects the error of the read data string corresponding to the true error detection result. Consequently, without extending the read cycle time, a refresh operation can be hid, and errors can be corrected simultaneously. By correcting a data error read from a bad memory cell of data retention characteristics, a refresh request interval can be extended, and power consumption during a standby period can be reduced.