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:
Apr. 30, 1996
Filed:
Jul. 12, 1995
Yasuhiro Nakakura, Osaka, JP;
Shouichi Yoshizaki, Osaka, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
In the case where an external signal line is driven by a circuit other than an output circuit with a voltage higher than an on-chip power-source voltage, if an output transistor is activated in the output state immediately after the driving of the external signal line by the above other circuit was cancelled, a voltage equal to or higher than the breakdown voltage of an oxide film of a transistor composing the output circuit is applied thereto. To prevent this, there is provided a voltage detecting means for detecting a voltage value of the above external signal line being higher than a value in the vicinity of the internal power-source voltage and generating a detection signal, which inhibits the activation of the output transistor. Consequently, in the output circuit of an LSI fabricated using submicron design rules, the application of a voltage equal to or higher than the breakdown voltage of an oxide film of each of the transistors composing the output circuit is prevented, resulting in increased reliability of the output circuit.