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:
Mar. 30, 1999
Filed:
Jul. 16, 1998
Kyoichi Shiota, Tokyo, JP;
Terunori Kubo, Tokyo, JP;
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
Provided is a data read circuit that can execute data reading under a proper reference voltage in the event that element characteristics have been changed due to aged deterioration. When a sample memory cell (10a) is selected, a memory transistor (26a) in which no electrons are injected into its floating gate, enters ON state. At this time, a voltage (V.sub.22) is inputted to an input terminal (22) of a sense amplification (18), and a control circuit (13) detects the voltage (V.sub.22) to store it as a digital signal. On the other hand, when a sample memory cell (10b) is selected, a memory transistor (26b) in which electrons are injected into its floating gate, does not enter ON state. As a result, a voltage (V.sub.11) is inputted as it is, to the input terminal (22). The control circuit (13) detects the voltage (V.sub.11) to store it as a digital signal. Based on the two digital signals, the control circuit (13) sets a reference voltage (V.sub.REF), and a reference voltage generating circuit (14) generates this reference voltage.