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. 06, 2004
Filed:
Oct. 07, 2002
Danny F. Ammar, Windermere, FL (US);
Ronald D. Graham, Clermont, FL (US);
Xytrans, Inc., Orlando, FL (US);
Abstract
A phase locked loop (PLL) frequency synthesizer generates a high frequency signal by generating an output signal from a voltage controlled oscillator of a primary phase locked loop (PLL) circuit. The voltage controlled oscillator output is programmably divided with a reference signal output at a divide ratio such that the outputs are equal to a common phase comparison frequency. An external reference signal used for the primary phase locked loop circuit is isolated by generating a voltage controlled, clean reference signal and filtering and synchronizing the clean reference signal with the external reference signal within a secondary phase locked loop circuit to produce the reference signal output to the primary phase locked loop circuit.