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:
Oct. 08, 1991
Filed:
Oct. 17, 1989
Gourab Majumdar, Itami, JP;
Shigekazu Yoshida, Itami, JP;
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
A MOS transistor (Q.sub.M) detects an increase of the collector current (I.sub.C) of an IGBT device (Q.sub.O). When an excess current passes, the transistor (Q.sub.M) turns on, which restricts the gate voltage (V.sub.G) of the IGBT device (Q.sub.O) to decrease the collector current (I.sub.C). This protects the IGBT device (Q.sub.O) from the excess current. A Zener diode (D.sub.Z) placed on a path which is for detecting the excess current of the IGBT device (Q.sub.O) restricts the current passing through the path. This decreases reactive power which is consumed in protecting the device (Q.sub.O) from the excess current while protecting a drive circuit from an erroneous operation.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile