Frequency-control circuits and signal generation devices using the same

摘要

A signal generation device is provided to generate an output signal with constant frequency. The signal generation device includes a frequency-control circuit and a voltage-controlled delay line. The frequency-control circuit is arranged to charge/discharge a voltage-control node according to a comparison result signal. The voltage-controlled delay line is arranged to generate a control signal according to the comparison result signal and a control voltage of the voltage-control node to control the output signal. A frequency of the control signal is modulated by the voltage-controlled delay line according to the control voltage of the voltage-control node. The comparison result signal is generated according to a difference between a reference voltage and a voltage level of the output signal.