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. 28, 2017
Filed:
Jun. 03, 2016
Xilinx, Inc., San Jose, CA (US);
Mayank Raj, San Jose, CA (US);
Parag Upadhyaya, Los Gatos, CA (US);
Adebabay M. Bekele, San Jose, CA (US);
XILINX, INC., San Jose, CA (US);
Abstract
An example phase-locked loop (PLL) circuit includes a voltage controlled oscillator (VCO) configured to generate an output clock based on an oscillator control voltage, a sub-sampling phase detector configured to receive a reference clock and the output clock, and a phase frequency detector configured to receive the reference clock and a feedback clock. The PLL circuit includes a charge pump configured to generate a charge pump current, a multiplexer circuit configured to select either output of the sub-sampling phase detector or output of the phase frequency detector to control the charge pump, and a lock detector configured to receive the reference clock, the feedback clock, and the output of the phase frequency detector to control the multiplexer. The PLL circuit includes a loop filter configured to filter the charge pump current and generate the oscillator control voltage, and a frequency divider configured to generate the reference clock from the output clock.