公开(公告)号：EP1925077A1

公开(公告)日：2008-05-28

申请号：EP06814487.2

申请日：2006-09-12

Applicant: Silicon Laboratories Inc.

Inventor： VANCORENLAND, Peter ,  LIM, Lysander ,  MARQUES, Augusto M. ,  WILLINHAM, Scott D.

IPC: H03J3/18 ,  H03B5/12 ,  H03L7/099

CPC classification number: H03J3/185 ,  H03B5/1243 ,  H03B5/1293 ,  H03B2200/0062 ,  H03B2201/0208 ,  H03B2201/0266 ,  H03J7/10 ,  H03J2200/36 ,  H03L7/099

Abstract: An oscillator includes a plurality of varactor cells to receive a control signal to control a frequency of the oscillator. Each of the varactor cells includes a switch that includes a first terminal to receive the control signal and a second terminal such that the switch operates to control a capacitance of the varactor cell in response to a voltage between the first and second terminals. The oscillator includes a bias circuit to provide a different bias voltage to each second terminal and an amplifier that is coupled to the varactor cells to generate an oscillating signal.