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:
May. 22, 2001
Filed:
Jan. 05, 2000
Kunihiro Katayama, Chigasaki, JP;
Takayuki Tamura, Yokohama, JP;
Satoshi Watatani, Yokohama, JP;
Kiyoshi Inoue, Tokyo, JP;
Shigemasa Shiota, Tachikawa, JP;
Masashi Naito, Kodaira, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A semiconductor memory device having an electrically erasable nonvolatile memory, wherein the nonvolatile memory has management information regions for individual blocks and fault registration regions for registering fault addresses. If a block is accessed and found to be faulty, the fault registration is performed so that a partially faulty memory can be used without an increase in access time. By registering the management information address for executing the interchanges of blocks in one-to-one correspondence in the administrative information region, moreover, the blocks can be interchanged depending upon the frequency of rewriting.