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. 01, 2006
Filed:
Jun. 01, 2004
Vladimir Prodanov, New Providence, NJ (US);
Vladimir Prodanov, New Providence, NJ (US);
Agere Systems Inc., Allentown, PA (US);
Abstract
A power device(s) is biased and operates in Class-AB. Crossover distortion is minimized over a broad range of operating conditions, not only for a nominal case. The bias current of a power transistor is automatically adjusted in response to process and temperature variations. Preferably, the adjustment is performed using an error-feedback arrangement. An exemplary 'rule' for bias adjustment involves satisfying a proportionality relationship between the small-signal device transconductance at the operating point, and a maximum device transconductance. A dual replica master-slave control architecture is utilized. A self-adapting circuit is provided to change the bias current (or voltage) so that the value is always the optimum value, irrespective of operating temperature and/or process variations. Self-biasing is introduced wherein no manual adjustment is necessary. A stable amplifier is formed having great robustness to process and temperature variations.