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:
Mar. 27, 2012
Filed:
Mar. 13, 2009
I-hsiang Lin, Mountain View, CA (US);
Roger Brockenbrough, Los Gatos, CA (US);
I-Hsiang Lin, Mountain View, CA (US);
Roger Brockenbrough, Los Gatos, CA (US);
Qualcomm Incorporated, San Diego, CA (US);
Abstract
A clock clean-up phase-locked loop (PLL) that may reduce spurs and improve performance of a receiver is described. In one exemplary design, an integrated circuit includes a PLL and an analog-to-digital converter (ADC). The PLL receives a first clock signal generated with a fractional divider ratio and having spurs due to abrupt frequency jumps. The first clock signal may be generated by a fractional-N frequency synthesizer external to the integrated circuit. The PLL generates a second clock signal with an integer divider ratio and having reduced spurs. The ADC digitizes an analog baseband signal based on the second clock signal and provides digital samples. The integrated circuit may further include a low noise amplifier (LNA), which may observe less spurs coupled via the substrate of the integrated circuit due to the use of the PLL to clean up the first clock signal.