A PLL comprising a phase detector, a loop filter and a VCO is disclosed. The phase detector periodically compares an externally inputted clock signal with a frequency of an internal clock signal, and outputs an output signal resulting from phase difference of the two signals. The loop filter outputs...http://www.google.fr/patents/US6967538?utm_source=gb-gplus-shareBrevet US6967538 - PLL having VCO for dividing frequency
