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:
Dec. 17, 2013
Filed:
Oct. 18, 2011
Kochung Lee, San Jose, CA (US);
Quan Yu, Shanghai, CN;
Yuntao Zhu, Shanghai, CN;
Lei Xie, Shanghai, CN;
Ming Qu, San Jose, CA (US);
Kochung Lee, San Jose, CA (US);
Quan Yu, Shanghai, CN;
Yuntao Zhu, Shanghai, CN;
Lei Xie, Shanghai, CN;
Ming Qu, San Jose, CA (US);
Parade Technologies, Ltd., Georgetown, Grand Cayman, KY;
Abstract
A system and method are disclosed for generating a high accuracy and low power on die reference clock. An LC clock is generated on die and a frequency divider lowers the LC clock frequency to a target reference frequency. An RCO clock is generated on die with an unknown initial frequency. The RCO clock and target reference clock are compared to determine in which direction the frequency of the RCO clock should be adjusted to move closer to the target reference frequency. A signal is sent causing a current source or capacitor in the RCO circuit to be modified. Therefore, the RCO clock frequency is adjusted. The RCO circuit is repeatedly adjusted until the RCO clock frequency is sufficiently accurate. The LC clock is disabled to conserve the power that would have been consumed in generating the LC clock.