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:
Apr. 28, 2009
Filed:
Apr. 26, 2007
Hung C. Ngo, Austin, TX (US);
Fadi H. Gebara, Austin, TX (US);
Jethro C. Law, Austin, TX (US);
Trong V. Luong, Austin, TX (US);
Hung C. Ngo, Austin, TX (US);
Fadi H. Gebara, Austin, TX (US);
Jethro C. Law, Austin, TX (US);
Trong V. Luong, Austin, TX (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A digital frequency multiplier circuit is disclosed. The digital frequency multiplier circuit includes a digitally controlled oscillator (DCO), a phase detector and a control circuit. The DCO generates an internal feedback signal. The phase detector detects a phase difference between the internal feedback signal and an external reference clock signal. Coupled between the phase detector and the DCO, the control circuit adjusts the DCO to align the internal feedback signal with the external reference clock signal after a phase difference between the internal feedback signal and the external reference clock signal has been detected. The control circuit also locks a modulation frequency of the DCO and monitors the state of the digital frequency multiplier circuit in order to maintain the lock.