Patent ID: 7692496

Claim:
A signal generating apparatus, comprising: a first detecting circuit configured to detect a rising edge phase difference of an input signal and a feedback signal to generate a first control signal, the first detecting circuit including: a first phase detector configured to detect the rising edge phase difference of the input signal and the feedback signal to generate a first detecting signal; and a first charge pump configured to generate the first control signal according to the first detecting signal; a second detecting circuit configured to detect a falling edge phase difference of the input signal and the feedback signal to generate a second control signal; a controllable oscillator configured to adjust an output oscillating signal according to the first control signal and the second control signal; a feedback circuit configured to generate the feedback signal according to the output oscillating signal; and a first bandwidth control unit configured to utilize the first detecting signal to generate a first bandwidth control signal to adjust a DC current of the first charge pump, wherein the first bandwidth control unit comprises: a phase generator, for generating a phase signal according to the first detecting signal; a charge pump, for generating the first bandwidth control signal according to the phase signal; and a filter, for filtering the first bandwidth control signal.