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. 04, 1991
Filed:
Dec. 09, 1988
Kenji Kohda, Hyogo, JP;
Tsuyoshi Toyama, Hyogo, JP;
Nobuaki Ando, Hyogo, JP;
Kenji Noguchi, Hyogo, JP;
Shinichi Kobayashi, Hyogo, JP;
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
A non-volatile memory cell includes a MOS transistor of double gate construction. The MOS memory transistor includes a floating gate structure which includes electrically separated first and second segmented floating gates (4a; 4b). For the purpose of writing data, electrons are independently injected into the first and second segmented floating gates. Data are stored in the MOS memory transistor in three different non-volatile storage levels; one with electron accumulated either one of the two segmented floating gates; another with electrons injected into both of the segmented floating gates; and still another with no electrons accumulated on both of the segmented floating gates.