| 摘要 |
<p>A reference frequency generator which outputs a first frequency signal, a PLL unit which outputs a phase error signal in accordance with the first frequency signal and a second frequency signal, a first filter which outputs a first smoothed phase error signal from the phase error signal outputted by the PLL section in accordance with a first reference, a second filter which outputs a second smoothed phase error signal from the phase error signal outputted by the PLL section in accordance with a second reference, switches which switch the first or second smoothed phase error signal outputted by the first or second filter between each other and output one of them, an output frequency generator which outputs a signal of the second frequency based upon the first or second smoothed phase error signal to the PLL section and a switching control section which controls the operation of the switches.</p> |
