| 摘要 |
PURPOSE:To improve lock characteristic of jitters or the like by providing a stable oscillation frequency by compensating a base current to be consumed by a delay amount control part by providing a voltage/current conversion circuit inside a ring oscillation voltage controlled oscillator circuit. CONSTITUTION:A ring oscillation voltage controlled oscillator circuit 10 adds voltage/current conversion circuits 12 equipped with base current correcting circuits 11 to current control terminals V2 at the differential parts of (n) stages of differential amplifiers 6. The circuit in Figure uses a Wilson's current mirror circuit composed of three transistors Q8, Q9 and Q10 and two resistors R1 and the current mirror circuit of a PNP transistor composed of two transistors Q13 and Q14 and two resistors R3. A voltage control terminal Vcont increases its impedance, and the oscillation frequency of the oscillator circuit 10 can be controlled only by the voltage. Even when the voltage/current conversion circuit 12 is connected to a current control terminal V1 at the emitter follower of the oscillator circuit 10, the similar effect can be provided. |
