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:
May. 26, 1998
Filed:
Mar. 26, 1997
Ryuichi Matsuo, Hyogo, JP;
Makoto Yamamoto, Hyogo, JP;
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
A non-volatile SRAM cell (MC) includes floating gate type transistors (1a, 1b) arranged between power supply nodes (4a, 4b) and storage nodes (A, B), and flip-flops (2a, 2b) holding signal potentials of the storage nodes. The floating gate type transistor has a drain connected to the power supply node, and a control gate connected to a control electrode node (5). Voltages are applied independently to the drains and the control gate of the floating gate type transistor, whereby a large amount of hot electrons are efficiently generated by avalanche breakdown and are accelerated to be injected into the floating gate. Removal of electrons is achieved by the voltages applied to the control gate and the drain. In the non-volatile SRAM cell utilizing the floating gate type transistor, injection and removal of electrons with respect to the floating gate are efficiently performed to change a threshold voltage for reliably storing information in a non-volatile manner.