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. 04, 1993
Filed:
Jan. 28, 1991
Applicant:
Inventors:
Assignee:
Mitsubishi Denki Kabushiki Denki, Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01L / ;
U.S. Cl.
CPC ...
257356 ; 257360 ; 257546 ;
Abstract
An input circuit of a semiconductor device includes a P type well formed on the main surface of a semiconductor substrate, and an N type region formed on the main surface in the P type well. A P-N junction is formed by the N type region and the P type well. An input voltage is applied to the N type region, which input voltage is applied to an internal circuit formed on the semiconductor substrate. When the P-N junction is rendered conductive by an application of an excessive voltage to the input voltage, the current caused by the excessive voltage is absorbed to the supply potential through the P type region formed in the P well.