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. 19, 2009
Filed:
Sep. 16, 2005
Yido Koo, Seoul, KR;
Youngho Ahn, Seoul, KR;
Eunseok Song, Seoul, KR;
Jeong-woo Lee, Seoul, KR;
Joonbae Park, Seoul, KR;
Kyeongho Lee, Seoul, KR;
Yido Koo, Seoul, KR;
Youngho Ahn, Seoul, KR;
Eunseok Song, Seoul, KR;
Jeong-Woo Lee, Seoul, KR;
Joonbae Park, Seoul, KR;
Kyeongho Lee, Seoul, KR;
GCT Semiconductor, Inc., San Jose, CA (US);
Abstract
A sigma-delta based phase lock loop device is provided that includes a phase frequency detector (PFD), a charge pump and a voltage controlled oscillator. The PFD to receive a reference signal and a feedback signal and to output signals based on a comparison of the reference signal and the feedback signal. The charge pump to output a charge based on the output signals from the PFD. The charge pump including a first current source to apply a fixed amount of current and a second current source to apply a variable amount of current. The voltage controlled oscillator to output a clock signal based on the received charge from the charge pump.