| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a PLL circuit capable of suppressing output noise without increasing circuit scale. <P>SOLUTION: A PLL circuit 1 according to the present invention includes: a phase comparator 11 detecting a phase difference between a reference signal Ref and a feedback signal FB; a charge pump 121 outputting a current Ipr according to the detection result of the phase comparator 11; a charge pump 131 outputting a current Iint according to the detection result of the phase comparator 11; a filter 122 outputting a current Iprop in which high frequency components of the output current Ipr of the charge pump 121 is removed; an integrator 132 integrating the output current Iint of the charge pump 131; a voltage-current conversion circuit 133 outputting a current Ivi according to the integration result of the integrator 132; and an oscillator 15 generating an oscillation signal with a frequency according to a current Iro generated by adding the current Iprop and the current Ivi and returning the signal to the phase comparator 11. <P>COPYRIGHT: (C)2013,JPO&INPIT |
