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:
Jul. 22, 2003
Filed:
Oct. 03, 2001
Bruce W. Carsten, Corvallis, OR (US);
Other;
Abstract
A bipolar junction transistor (BJT) used as a controlled rectifier (CR) that is driven and controlled by an electronic circuit, such that when (in a first mode of operation) the collector-emitter voltage (VCE) is above an offset voltage (VCEOS) the circuit drives the base of the SR BJT with a base current proportional to the difference between VCE and VCEOS, turning the CR BJT on with a base current proportional to the collector current. When the VCE of the CR BJT falls below VCEOS the drive circuit turns on a second transistor coupled between the base and collector of the CR BJT to turn the CR BJT rapidly off and maintains it in the off state as the collector voltage reverses. When the VCE of the CR BJT exceeds a threshold voltage above the normal conduction VCE range, the control circuit increases the base drive current to accelerate the CR BJT turn-on process. A second mode of operation occurs in the presence of an “OFF” drive command to the CR, which turns the CR off when the collector voltage is above the emitter voltage. Turn off of the CR is now accomplished with a third transistor coupled between the base and emitter of the CR BJT.