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. 08, 1999
Filed:
Dec. 23, 1997
Hitoshi Irino, Tokyo, JP;
NEC Corporation, Tokyo, JP;
Abstract
Protection circuits for preventing an internal circuit on a semiconductor substrate from destroying due to an excess voltage are formed on the output end and input end of an internal circuit. The protection circuit on the input end has a gate electrode comprised of a band-like conductive film. This gate electrode is grounded and has a shape zigzagging in a waveform with crests and troughs alternately appearing in a planar view. A drain diffusion layer connected to an output end of the internal circuit is formed in one of two diffusion regions of the surface of the semiconductor substrate that are defined by the gate electrode, and a source diffusion layer grounded is formed in the other region. The source diffusion layer and the drain diffusion layer are formed integral with each other, so that the protection circuit on the input end is substantially constituted of one buffer transistor.