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:
Dec. 17, 2002
Filed:
Apr. 10, 2001
Kenji Hibino, Tokyo, JP;
NEC Corporation, Tokyo, JP;
Abstract
A semiconductor memory device ( ) having an array of ROM cells ( ) based on a flat cell architecture has been disclosed. Semiconductor memory device ( ) can include a y-selector ( ) coupled between a sense amplifier ( ) and array ( ). During a read operation, the y-selector can electrically connect a selected digit line (D ) and an adjacent digit line (D ) to the sense amplifier. Y-selector ( ) can couple a next digit line (D ) to a precharge voltage that may be supplied by a precharge circuit ( ). A virtual ground selector ( ) can apply a ground voltage level from a main virtual ground line (VG ) to sources of a column of memory cells including a selected memory cell ( ). Virtual ground selector ( ) can apply a precharge voltage to an adjacent main virtual ground line (VG ). In this manner, a minimum sensing current, when a series of memory cells along a selected word line (W ) are on-bit cells, can be improved.