The present invention provides a method and an apparatus for selectively
pretuning and updating a phase lock loop, deployed in an integrated
circuit including an agile radio, such as a wideband or an ultra wideband
frequency agile radio in a telecommunication system, for example, a
reconfigurable multiband and/or multistandard mobile communication
system. In one embodiment, a phase lock loop may comprise a digital
storage having a first desired frequency. An oscillator may provide an
oscillator frequency and a frequency generator circuit capable of
producing at least one control signal may cause the oscillator to adapt
the oscillator frequency based on the first desired frequency in response
to a trigger signal. A pretune unit may apply a pretune voltage to a
tuning element to cause the oscillator to calibrate the oscillator
frequency to the first desired frequency. An output voltage may be added
at the output of a loop filter to the pretune voltage to tune the output
voltage of the loop filter such that to set the oscillator frequency
substantially at the first desired frequency. An update unit may
automatically determine whether one or more parameters of a phase lock
loop unit have changed to dynamically update the pretune voltage.