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:
Jun. 01, 1993
Filed:
May. 02, 1991
Samsung Electronics Co., Ltd., Kyunggi, KR;
Abstract
In a nonvolatile semiconductor memory device having a plurality of word lines, bit lines, sense lines, nonvolatile semiconductor memory cells, column selecting transistors, a page buffer circuit, data lines, an input driver/sense amplifier, an input buffer an input/output register and a comparator, a secret access code is defined in such a manner that a first secret access code is latched in the page buffer circuit, a second secret access code inputted by the input buffer is compared with the first secret access code read by the input/output register by bytes in the comparator, and if the first and second access codes match, the first secret access code latched in the page buffer is written in the cells of the row line designated in advance among the nonvolatile memory cells.