Abstract: A PLL comprises a VCO and a loop filter, wherein the VCO generates an AC output signal having a frequency which depends on an applied control voltage, and wherein the loop filter provides a control voltage to the VCO. The control voltage reflects determined phase differences between a potentially frequency divided output signal of the VCO and a reference signal. When operating the PLL, frequency deviations between a potentially frequency divided output signal of the VCO and a reference signal are detected and in addition, a resolution employed for detecting the frequency deviations is lower than a resolution employed for determining the phase differences. In case a frequency deviation is detected, a direct-current voltage shift is added to the control voltage provided by the loop filter.

Abstract: A PLL comprises a VCO and a loop filter, wherein the VCO generates an AC output signal having a frequency which depends on an applied control voltage, and wherein the loop filter provides a control voltage to the VCO. The control voltage reflects determined phase differences between a potentially frequency divided output signal of the VCO and a reference signal. When operating the PLL, frequency deviations between a potentially frequency divided output signal of the VCO and a reference signal are detected and in addition, a resolution employed for detecting the frequency deviations is lower than a resolution employed for determining the phase differences. In case a frequency deviation is detected, a direct-current voltage shift is added to the control voltage provided by the loop filter.

Abstract: A method and a device for filtered sync signals detection wherein a timing circuit is used to select the steep slope portion in one or both of the leading edge and the trailing edge of the sync signals; a voltage divider or feedback path to set a triggering point at the steep slope portion of the selected edge regardless the slope being positive or negative; and a triggerable device is used to generate new sync signals with the leading edge of each sync pulse starts at one triggering point and the trailing edge starts at another triggering point. Alternatively, a micro-controller is used to detect the polarity of the sync signals and accordingly provide a reference voltage in order to set the triggering point at the leading edge of the sync signals.