Patent ID: 7138877
Filing Date: 2006-11-21
Classification: H03L,H04L

Abstract:
1. A phase locked loop circuit, comprising: a phase-frequency detector to provide a phase difference signal in response to an input signal and a feedback signal; a charge-pump, coupled to the phase-frequency detector, to provide a first voltage in response to the phase difference signal; a filter, coupled to the charge-pump, to provide a second voltage in response to the first voltage; a first voltage-controlled oscillator, coupled to the filter, to provide the feedback signal in response to the second voltage; a second voltage-controlled oscillator, coupled to the filter, to provide the feedback signal in response to the second voltage; and, a multiplexer, coupled to the first and second voltage-controlled oscillators, to provide the feedback signal in response to the control signal, wherein the charge-pump includes a gain that is adjustable in response to a control signal.