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:
Nov. 17, 2009
Filed:
Jul. 29, 2005
Vincent Thiery, La Roque d'Antheron, FR;
David Jacquinod, La Fare les Oliviers, FR;
Vincent Thiery, La Roque d'Antheron, FR;
David Jacquinod, La Fare les Oliviers, FR;
International Rectifier Corporation, El Segundo, CA (US);
Abstract
A circuit protective device includes a current sensing circuit adapted to be coupled to an output power switch to provide a feedback signal representative of the output current, an overcurrent sensor responsive to the feedback signal exceeding a presettable reference level to provide an overcurrent alert signal, a function generator responsive to the feedback signal to generate a first signal related to the output current according to a preset functional relationship, an integration circuit coupled to the output of the function generator to provide a second signal representative of the product of the first signal and t, where t is the elapsed time following generation of an overcurrent alert signal, and a control circuit responsive to a presettable value of the second signal to disable a gating circuit for the power switch, the shut-down signal being provided at a time which depends on the magnitude of the overcurrent signal. The control circuit also shuts down the gating circuit if the output current exceeds a second preset limit representing a short circuit condition with substantially no delay. A related method, and a function generator in the form of a piece-wise linear approximation circuit are also disclosed.