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:
May. 12, 2015
Filed:
Apr. 30, 2013
Micrel, Inc., San Jose, CA (US);
Juinn-Yan Chen, Fremont, CA (US);
Wei-Kang Cheng, Milpitas, CA (US);
Micrel, Inc., San Jose, CA (US);
Abstract
A phase-locked loop circuit using a multi-curve voltage-controlled oscillator (VCO) having a set of operating curves, each operating curve corresponding to a different frequency range over a control voltage range. The phase-locked loop circuit includes a digital control circuit configured to generate a curve select signal using a closed loop curve search operation to select one of the operating curves in the multi-curve VCO, the selected operating curve being used by the VCO to generate an output signal with an output frequency being equal or close to a target frequency of the phase-locked loop. In one embodiment, the digital control circuit implements a binary jump method and an operating curve is selected when the operating curve has an output frequency meeting the target frequency with the control voltage being within a first voltage range being a narrowed and centered voltage range within the control voltage range.