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. 02, 1977
Filed:
May. 27, 1976
Hitachi, Ltd., , JA;
Abstract
A semiconductor bidirectional switch circuit comprises a bidirectional switch including two thyristors connected in antiparallel relationship. A bypass circuit is connected to each of the two thyristors for bypassing a part of a main current flowing through the thyristor from the anode to the cathode of the thyristor. A cathode-gate driver circuit is connected to the cathode-gate of each of the two thyristors for supplying a current thereto and a driver circuit is connected to the base of the transistor constituting each of the two bypass circuits, for extracting a current from the base, whereby the gate current of either of the thyristors is allowed to continue flowing at a low drive voltage irrespective of the amplitude of an AC signal voltage which passes through the bidirectional switch circuit so that even when the AC signal current decreases in absolute value below the self-holding current of the thyristor associated, the AC signal may be passed through the thyristor switch without being subjected to instantaneous interruptions.