| 摘要 |
PURPOSE:To generate a clock with a fast reply to a phase fluctuation by providing a phase modulation means receiving a phase of a clock outputted from a voltage controlled oscillator means and receiving an error signal outputted from a phase comparison means as a modulation input to the generator. CONSTITUTION:A clock outputted from a voltage controlled oscillator 53 is inputted to a phase modulator 56. Moreover, a phase error signal outputted from a phase comparator 51 is inputted to the phase modulator 56 after the gain is adjusted to a prescribed gain by a gain adjustment device 55. The phase modulator 56 applies phase modulation to the clock inputted from the voltage controlled oscillator 53 corresponding to a modulation signal inputted from the gain adjustment device 55. Thus, a phase error difficult to be fallowed by a PLL circuit is corrected by an open servo loop by the phase modulator 56 to decrease the phase error further more. |
