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:
Apr. 07, 1998
Filed:
May. 23, 1996
Akira Nishiura, Nagano, JP;
Tatsuhiko Fujihira, Nagano, JP;
Fuji Electric Co., Ltd., Tokyo, JP;
Abstract
A semiconductor apparatus includes an insulated gate semiconductor device used as a power device and a pn diode used as a temperature sensor on a single semiconductor substrate. Heat generated in the power device is conducted to the temperature sensor. The voltage across a forward biased pn diode fed by a constant current source is sensitive to temperature. The temperature of the power device is measured by feeding a small current from a constant current supply to the pn diode and by detecting the forward voltage of the pn diode. When the forward voltage reaches a predetermined value, an external protection circuit is activated to prevent overheating. Multiple pn diodes may be connected in series to detect the temperature of multiple power devices more accurately.