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:
Oct. 09, 1990
Filed:
Apr. 12, 1988
Giampietro Maggioni, Cornaredo, IT;
Fabio Marchio, Gallarate, IT;
Marco Morelli, Livorno, IT;
Francesco Tricoli, Milan, IT;
Abstract
A circuit for recirculating an inductive load's (L) discharge current through the driving power switching transistor (Tpw) utilizes a control transistor (Tc) of opposite polarity to that of the power transistor and capable of withstanding a minimum fraction (1/.beta.) of the discharge current. The circuit has the advantage of allowing recirculation of current with a fixed overvoltage independent of the value of the supply voltage, without requiring additional power devices. The circuit may also be provided with means (D1, D2 and DZ1) to turn-on the control transistor in the presence of concomitant supply overvoltages to protect the power device from dumping effects.