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. 08, 1988
Filed:
Jul. 16, 1986
Josef Einzinger, Unterschleissheim, DE;
Christine Fellinger, Unterhaching, DE;
Ludwig Leipold, Munich, DE;
Jenoe Tihanyi, Munich, DE;
Roland Weber, Munich, DE;
Siemens Aktiengesellschaft, Berlin and Munich, DE;
Abstract
The temperature of the power semiconductor component is sensed by a bipolar transistor. The bipolar transistor is in series with a depletion mode MOSFET whose gate and source electrodes are connected together. The drain electrode is also connected to a threshold element. Normally, the FET has low impedance, so that at the input of the threshold element source potential, e.g. ground potential, is present. With current rising as a function of temperature, the current through the FET is limited to a constant, essentially temperature-independent value, and the potential at the input of the threshold element rises steeply. This condition is detected as an overtemperature signal.