Patent ID: 6807245
Filing Date: 2004-10-19
Classification: H03L,H04L

Abstract:
A Phase Locked Oscillator (PLO) device for performing clock recovery based on an input signal, comprising:a first voltage detection section including a shifted data generation part for shifting input data with use of recovered clock to generate shifted data, a first phase comparison part for comparing phases of the input data and the shifted data with each other and outputting first difference data, and a first filter for removing an alternating-current component from the first difference data and outputting a first detection voltage; a second voltage detection section including a delay part for delaying the input data for a time corresponding to half of one time slot with use of an analog delay element and outputting delayed data, a second phase comparison part for comparing phases of the input data and the delayed data with each other and outputting second difference data, and a second filter for removing an alternating-current component from the second difference data and outputting a second detection voltage; an arithmetic section for dividing the first detection voltage by the second detection voltage to obtain a control voltage; and a clock oscillation section for outputting the recovered clock with an oscillation frequency thereof varied in accordance with the control voltage.