Patent ID: 6356612
Filing Date: 2002-03-12
Classification: H03L,H04L

Abstract:
A clock signal reproducing apparatus for reproducing a clock signal from a received bit stream signal, which comprises:an oscillator for generating the clock signal having a frequency which is substantially the same as the bit rate of the bit stream signal and varies in accordance with a control voltage applied thereto; a signal variation direction detection circuit for detecting whether an amplitude of the bit stream signal is increased or decreased during one period of the clock signal and outputting a variation direction signal representing a result of the detection; an analog-to-digital converter for converting the bit stream signal to a digital signal in synchronism with the clock signal; and an oscillator control circuit for supplying said oscillator with the control voltage corresponding to a value of the digital signal and a value of the variation direction signal, wherein whether to ascend or descend the control voltage according to an increase in the value of the digital signal is determined by the oscillator control circuit on the basis of the value of the variation direction signal.