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:
Jun. 17, 2014
Filed:
Mar. 15, 2013
Analog Devices, Inc., Norwood, MA (US);
Robert Schell, Chatham, NJ (US);
Analog Devices, Inc., Norwood, MA (US);
Abstract
Apparatus and methods for quadrature clock signal generation are provided. In certain implementations, an apparatus includes an invertible sine shaping filter configured to receive an in-phase clock signal, a quadrature-phase clock signal, and an inversion control signal. The invertible sine-shaping filter is further configured to filter the in-phase and quadrature-phase clock signals to generate sinusoidal in-phase and quadrature-phase clock signals. The invertible sine-shaping filter is further configured to selectively invert one or both of the in-phase and quadrature-phase clock signals based on an inversion control signal. The apparatus further includes a phase interpolator configured to generate an interpolated clock signal based on a weighted sum of the selectively inverted sinusoidal in-phase clock signal and the quadrature-phase sinusoidal clock signal. The in-phase clock signal and the quadrature-phase clock signal have a quadrature-phase relationship.