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. 28, 2003
Filed:
Mar. 30, 2000
Toshio Yamamura, Yokohama, JP;
Yoshihisa Sugiura, Kamakura, JP;
Kazuhisa Kanazawa, Fujisawa, JP;
Koji Sakui, Tokyo-To, JP;
Hiroshi Nakamura, Kawasaki, JP;
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Abstract
A memory cell array is divided into left and right cell arrays, each of which includes a plurality of blocks. Data erase is sequentially controlled by an erase control circuit on the basis of an erase command flag incorporated into a command register and an address incorporated into an address register. Batch erase is carried out with respect to selected blocks of the right and left cell arrays. After data erase, a verify operation is carried out with respect to the erased blocks by retrieving the erased blocks simultaneously with respect to the right and left cell arrays in parallel. Thus, the time required to retrieve the selected blocks for the verify operation after data erase is shortened, so that the time required to carry out the whole data erase is shortened.