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:
Jan. 16, 1996
Filed:
Sep. 16, 1993
Chihiro Okado, Tokyo, JP;
Makoto Hideshima, Tokyo, JP;
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Abstract
An overcurrent protection circuit for a power transistor for generating a main current in response to a gate drive voltage generated by a gate circuit. The overcurrent protection circuit includes a current detection circuit for detecting the main current flowing in the power transistor to generate a detection voltage corresponding to the main current, and a level detection circuit connected to receive the detection voltage for generating a control current corresponding to a difference between the detection voltage and a prescribed value when the detection voltage exceeds the prescribed value. The overcurrent protection circuit further includes a current control circuit connected to receive the control current for limiting the main current by regulating the gate drive voltage based on the control current, and a drive instruction control circuit connected to receive the control current for making the main current zero by controlling the gate drive voltage to an OFF condition based on the control current.