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:
Nov. 27, 2012
Filed:
Aug. 02, 2011
Evgueni Ivanov, Wilmington, MA (US);
Evgueni Ivanov, Wilmington, MA (US);
Analog Devices, Inc., Norwood, MA (US);
Abstract
Apparatus and methods for biasing amplifiers are provided. In certain implementations, a bias circuit is provided for controlling the drain-source voltage of input transistors electrically connected to the inputs of a transconductance amplification circuit. For example, the bias circuit can maintain a relatively constant drain-source voltage in the input transistors by using a feedback loop that includes a feedback amplifier for adjusting the bias current of the input transistors based upon a difference between the drain and source voltages of the input transistors. In certain implementations, the feedback amplifier has an offset voltage equal to about the desired value of the drain-source voltage, and the feedback amplifier is configured to adjust the bias current until the difference between the inputs of the feedback amplifier is equal to about the offset voltage.