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:
Sep. 25, 1984
Filed:
Jul. 23, 1982
Gerd Thiele, Erlangen, DE;
Siemens Aktiengesellschaft, Munich, DE;
Abstract
A firing circuit for two antiparallel-connected power thyristors. Each of the power thyristors has a gate terminal; the gate terminals being connected by a series combination of auxiliary thyristors. Each of the auxiliary thyristors is of the type which can withstand firing resulting from excessive anode cathode potential; the sum total of the anode cathode potentials of the series-connected auxiliary thyristors being less than the anode-cathode breakdown voltages of the power thyristors. This, while a power thyristor is in a nonconductive state, an anode-cathode voltage is impressed thereacross in the forward conduction direction. At an anode-cathode voltage which is less than the breakdown voltage of the power thyristor, the auxiliary thyristors are fired so as to form a conductive path which includes the cathode-gate path of the other power thyristor, the auxiliary thyristors, and the gate-cathode path of the protected thyristor. Normal firing of the power thyristor is achieved via the auxiliary thyristors, which may be fired by light pulses or current pulses. Thus, the auxiliary thyristors perform protective and normal firing operations.