Timing signal recovery circuit for a data transmission system

Abstract From the Canadian patent

A timing signal recovery circuit of the invention comprises a voltage-controlled oscillator (VCO) for generating a local timing signal in a receiver, and a phase-difference detector for generating a phase difference signal in response to the phase difference between the received signal and the generated local timing signal. The phase difference signal is applied to a loop filter to generate a VCO control signal. In the present invention a filter control circuit for generating a filter control signal in response to the VCO control signal, is provided in order to prevent the occurrence of the unstable condition of the receiver which may occur when the loop filter generates the VCO control …