June 17, 2003. 14 pages. Also available from the United States Patent and Trademark Office. Website: http://www.uspto.gov.
NOTE: At the time of publication, the author Vladimir Prodanov was not yet affiliated with Cal Poly.
A system, method and apparatus are disclosed for common-mode voltage feedback. The preferred system includes a plurality of differential circuits, a corresponding plurality of common-mode voltage detectors, a corresponding plurality of buffer circuits, and a common-mode control circuit. Each differential circuit is operative to produce a first differential output voltage and a second differential output voltage. Each corresponding common-mode voltage detector is operative to provide a common-mode voltage from the first differential output voltage and the second differential output voltage. The common-mode control circuit provides a control voltage signal from the common-mode voltage and from a reference voltage. Each buffer circuit is operative to adjust the corresponding common-mode voltage using the control voltage signal to provide a common-mode feedback voltage signal to the corresponding differential circuit.
Electrical and Computer Engineering