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:
Oct. 27, 1998
Filed:
Jan. 10, 1997
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
In a confirmation operation of write data after writing data into a memory cell transistor (a verify operation), a verify potential generation circuit supplies a verify potential VPVRFY to the control gate of a memory transistor. Verify potential VPVRFY is determined depending upon the resistance ratio of variable resistors and a value of a constant current supplied from a constant current source circuit. According to reduction of a power supply potential, potential VPVRFY is decreased. The conductance of a memory cell transistor is adjusted according to variation in a detection sensitivity of a sense amplifier according to variation in the power supply potential, whereby the cell threshold value after a write operation takes a constant value.