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:
Aug. 06, 2019
Filed:
Sep. 29, 2016
Fuji Electric Co., Ltd., Kawasaki-shi, Kanagawa, JP;
Masahiro Taoka, Matsumoto, JP;
FUJI ELECTRIC CO., LTD., Kawasaki-shi, Kanagawa, JP;
Abstract
A signal indicating temperature of an IGBT chip, after input into an overheat detection terminal, is simultaneously input into a first comparator for protection operation and a second comparator for precaution. At a normal time when the chip temperature is low, a first transistor connected to an alarm signal output terminal via a resistor and a second transistor connected to the alarm signal output terminal via a Zener diode are turned off, and the alarm signal output terminal whose voltage is pulled up by an external pull-up circuit is set to high level voltage. When the second comparator detects a precaution condition, the second transistor is turned on, and the alarm signal output terminal is set to intermediate level voltage. When the first comparator detects chip overheat, the first transistor is turned on, and the alarm signal output terminal is set to low level voltage.