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. 29, 2008
Filed:
Apr. 25, 2007
Joseph Michael Hensley, Lexington, NC (US);
Michael R. Elliott, Summerfield, NC (US);
Joseph Michael Hensley, Lexington, NC (US);
Michael R. Elliott, Summerfield, NC (US);
Analog Devices, Inc., Norwood, MA (US);
Abstract
Control structures are provided to accurately maintain amplifier common-mode levels at the predetermined level of a common-mode reference voltage V. The disclosed control structures provide amplifier feedback along a first feedback path that is configured to provide high gain and low bandwidth to closely maintain amplifier common-mode level at the predetermined level of a common-mode reference voltage V. They also provide amplifier feedback along a second feedback path that is configured to provide wide bandwidth to substantially reduce perturbations of the common-mode level that would have otherwise been induced by input signal transients. In an important amplifier feature, these controls are obtained without use of structures (e.g., capacitors and switching transistors) that use substantial current which reduces amplifier efficiency. Although the disclosed control structures may be used in a variety of systems, they are particularly suited for use in samplers and converter stages of pipelined analog-to-digital converters.