| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a VCO circuit that suppresses the generation of phase noise and a variation in oscillation frequency. <P>SOLUTION: In an embodiment, the VCO circuit comprises a ring oscillator 1 comprising three inverters IV1-IV3 connected in a ring, and a control current generation section 2 voltage/current-converts an input control voltage Vct to generate a control current Ict, which is supplied to the ring oscillator 1 as a supply current. In the VCO circuit, a constant current generation section 3 generates a constant current Ia, which is supplied to the ring oscillator 1 as a supply current to be superimposed on the control current Ict. <P>COPYRIGHT: (C)2013,JPO&INPIT |
