Patent ID: 7711340
Filing Date: 2010-05-04
Classification: H03L

Abstract:
1. A phase locked loop, comprising: a loop filtering a charge pump output signal to generate a voltage signal; a voltage-controlled oscillator configured to operate in a given one of a plurality of frequency zones, the given frequency zone within which the voltage-controller oscillator is operating in being based on a voltage level of the voltage signal, the voltage-controlled oscillator outputting an oscillator signal at a frequency corresponding to the voltage level of the voltage signal output from the loop filter; and a frequency zones control unit, connected to the loop filter, receiving the voltage signal of the loop filter as an input, outputting an N-bit zone control signal to select one of the plurality of the frequency zones, the N-bit zone control signal being adjusted in response to the voltage level of the voltage signal, wherein the frequency zones control unit includes: