CIRCUIT DEVICE FOR GENERATING TUNED VOLTAGE

摘要

PURPOSE: To prevent the substantial change of the loop amplification degree despite the switching of cut-off frequency of a phase control loop for a circuit which generates the tuning voltage of a voltage controlled oscillator. CONSTITUTION: The changeover switches 21 and 22 which are prepared at the output side of a phase detector 5 and the input side of an oscillator 1 perform the switching between the loop filters 23, 24... and the LPF 25, 26.... The loop filters never change the absolute value of their amplification degrees despite the change of the cut-off frequency.