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. 17, 2012
Filed:
May. 05, 2008
Chia-liang Lin, Fremont, CA (US);
Chi-kung Kuan, Fremont, CA (US);
Chia-Liang Lin, Fremont, CA (US);
Chi-Kung Kuan, Fremont, CA (US);
Realtek Semiconductor Corp., Hsinchu, TW;
Abstract
A digitally controlled oscillator provides high resolution in frequency tuning by using a digitally controlled capacitive network that includes a tunable capacitive circuit, a first capacitor and a second capacitor. The tunable capacitive circuit generates a variable capacitance according to a digital control word. The first capacitor is coupled in an electrically parallel configuration with the tunable capacitive circuit. The second capacitor is coupled in an electrically serial configuration with a combination of the first capacitor and the tunable capacitive circuit. The first capacitor and the second capacitor are sized such that an effective capacitance of the digitally controlled capacitor network has a step size that is a fraction of a step size of the variable capacitance in response to an incremental change in the digital control word.