Patent ID: 7120412
Filing Date: 2006-10-10
Classification: H03B,H03J,H03L,H04B

Abstract:
1. A phase-locked loop system formed within a radio receiver, comprising: a phase-locked loop circuit for providing a signal having a specified frequency characteristic; a voltage controlled oscillator calibration circuitry for providing a calibration output signal to the phase-locked loop circuit that specifies how many selectable capacitors of a plurality of capacitors formed within the phase-locked loop circuit are to be selectively coupled to a node within the phase-locked loop circuit while the phase-locked loop system is operating in a calibration mode; wherein the voltage controlled oscillator calibration circuitry further includes a finite state machine is coupled to receive a first control signal and is formed to initiate a calibration process whenever the first control signal is received; and wherein the voltage controlled oscillator calibration circuitry further includes a plurality of comparators, the plurality of comparators being coupled to receive a VCO voltage and each coupled to receive one of a plurality of threshold voltages for comparing to the VCO voltage.