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:
May. 01, 1990
Filed:
Apr. 13, 1989
Haruyoshi Mori, Kobe, JP;
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
Disclosed is an overvoltage suppressing circuit for a semiconductor device connected between the poles of a DC power source and adapted to effect a switching operation. The circuit comprises: a serial circuit connected in parallel with a semiconductor device and including an overvoltage suppressing capacitor, an oscillation suppressing diode, and an impedance regulator connected in series each other, the impedance regulator being operable to change into a state of high impedance for suppressing a reverse current flowing into the oscillation suppressing diode when the oscillation suppressing diode is turned off; and a discharging device connected between a DC power source and the overvoltage suppressing capacitor for discharging to the DC power source a charge accumulated in the overvoltage suppressing capacitor when the oscillation suppressing diode is off.