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. 13, 1984
Filed:
Nov. 06, 1981
Masahiro Ogata, Kodaira, JP;
Osamu Sakai, Kodaira, JP;
Hitachi, Ltd., Tokyo, JP;
Hitachi Microcomputer Engineering, Ltd., Tokyo, JP;
Abstract
In the past, it has been a problem in integrated circuits using MOSFETs that the gate insulating film of a transmission gate MOSFET is broken down when an abnormally high voltage such as is caused by frictional static electricity is applied to its drain region. This breakdown of the gate insulating film cannot be prevented merely by limiting the voltage level applied to the drain region to a level below the breakdown withstand voltage of the gate insulating film. The reason for this is that even with such voltage limiting, the breakdown of the gate insulating film can still occur when local heating is generated by a relatively large breakdown current flowing through the drain junction. To prevent such a breakdown of the gate insulating film, therefore, a resistance element for limiting the breakdown current is connected in series with the drain region of the transmission gate MOSFET.