公开(公告)号：EP1803186A2

公开(公告)日：2007-07-04

申请号：EP05800772.5

申请日：2005-09-21

申请人： GCT Semiconductor, Inc.

发明人： Park, Joonbae ,  Lee, Seung-Wook ,  Lee, Jeong-Woo ,  Lee, Kyeongho

IPC分类号： H01P5/12

CPC分类号： H03L7/113 ,  H03L7/087 ,  H03L7/10 ,  H03L7/187

摘要： An apparatus for oscillating a frequency, which comprises a phase lock loop, see fig. 5, a variable frequency divider() is shown, that divides a first frequency (Fout) signal by a division ratio to generate a second frequency signal, this based on a comparison of reference frequency clock input (Fref) and feedback input to phase/frequency detector (510). A charge pump (520) and loop filter (530) are shown with a divider (550) that divides the second frequency signal (355) to allow the correct feedback frequency to be realized. The VCO (540) inherently has a resonant circuit including the capacitors to be selected and a corresponding control voltage to set the frequency of operation as well as an active circuit (320) for proper gain.