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:
Jul. 27, 2004
Filed:
Mar. 05, 2003
Poongyeub Lee, San Jose, CA (US);
Joo Weon Park, Pleasanton, CA (US);
Kwangho Kim, Sunnyvale, CA (US);
Eungjoon Park, Fremont, CA (US);
NexFlash Technologies, Inc., San Jose, CA (US);
Abstract
In an array of nonvolatile memory cells, as many memory cells as desired and indeed even the entire array of memory cells may be placed in a single region of the bulk, illustratively a p-well. Peripheral circuitry is used to in effect section the memory array into blocks and groups of blocks, and to establish suitable biasing and counter-biasing within those blocks and groups during page or block erase operations to limit erase disturb. Each group is provided with its own set of voltage switches, which furnishes the bias voltages for the various modes of operation, including erase. Each of the voltage switches furnish either a large positive voltage when its group is selected, or a large negative voltage when its group is unselected. The size of the group is established as a compromise between degree of erase disturb and substrate area required for the voltage switches.