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. 14, 2001
Filed:
Feb. 04, 2000
Oleksiy Zabroda, Kanata, CA;
STMicroelectronics, Inc., Carrollton, TX (US);
Abstract
A pair of equivalent controlled impedance buffers are connected in a push-pull configuration to a transformer primary coil. A pair of equivalent pre-drivers are connected to the pair of buffers. Each pre-driver receives a driver input signal and outputs a buffer input signal and a proportional flyback compensation signal. Each buffer receives the buffer input signal generated from one of the pre-drivers for buffered output as a line driver signal to the primary coil which induces a flyback voltage effect in each buffer. Each buffer further receives the flyback compensation signal generated from the other one of the pre-drivers, with the buffer operating to cancel the flyback voltage effect induced in that buffer using the flyback compensation signal received from the other one of the pre-drivers. An adjustment circuit further outputs an adjustment signal for application to an adjustable current source. By manipulating the adjustable current source with the adjustment signal, the output impedance of the buffer can be made to match the characteristic impedance of a transmission line connected to the transformer secondary coil.