VOLTAGE CONTROLLED OSCILLATOR USING NEGATIVE - RESISTIVE FEEDBACK

摘要

A voltage controlled oscillator (VCO) including a negative feedback circuit 12 operates in response to a negative feedback signal generated during active transistor region operation of transistors in transconductance amplifying stages 10 and 11. As a result, harmonic distortion and problems of noise and unstable frequency oscillation are obviated or significantly reduced. The VCO includes first and second variable transconductance (gm) amplifying stages whose non-inverting (+) and inverting (-) terminal are respectively grounded and a first condenser circuit connected between an output terminal of the first transconductance amplifying stage and a non-inverting (+) terminal of the second transconductance (gm) amplifying stage. 12 is a negative-resistive circuit.