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:
Aug. 07, 1984
Filed:
Aug. 22, 1983
Nagataka Seki, Tokyo, JP;
Tokyo Shibaura Denki Kabushiki Kaisha, Kawasaki, JP;
Abstract
A gate circuit of a gate turn-off thyristor has first and second circuit means. The first circuit means consists of a diode, a pulse transformer with a voltage dividing point in the primary section, and a switching element. The transformer provides a pulse current of a large rising rate between the cathode and gate of the thyristor when the switching element is closed and also provides a pulse current of a smaller falling rate between the cathode and gate when the switching element is open. The second circuit means consists of at least a single capacitor, which is connected between the voltage dividing point of the transformer and a d.c. power supply feeding an electrical power to the two circuit means so as to produce a higher voltage than that of the power supply at one end of the primary section, which is blocked by the diode from the power supply, when the switching element is open, and so as to discharge down to a lower voltage than that of the power supply at one end of the primary section when the switching element is closed.