Voltage-controlled oscillator circuit which compensates for supply voltage fluctuations

摘要

A voltage-controlled oscillator circuit compensates for supply voltage fluctuations of the oscillator and thus for frequency fluctuations at the oscillator output. An additional voltage-controlled capacitor is connected in parallel with the voltage-controlled capacitor of the LC resonant circuit. The control terminal of the second voltage-controlled capacitor is coupled to the supply voltage terminal, which feeds the oscillator circuit. The oscillator circuit can be monolithically integrated and can be employed in phase-locked loops, for example.