HIGH FREQUENCY CMOS VCO HAVING GAIN CONSTANT AND DUTY CYCLE COMPENSATION

摘要

PURPOSE: To provide a high frequency CMOS voltage controlled oscillator circuit having gain constant and duty cycle compensation. ;CONSTITUTION: A multi-stage oscillator 26 has plural inverter stages connected in series, which have N channel and P channel transistors. The ring oscillator 26 controls the vibration frequency of the ring oscillator in response to a control current signal. A process compensation circuit supplies a current dump output signal corresponding to the channel intensity of the P channel and N channel transistors in response to a tuning voltage input signal. A trip point compensation circuit 24 supplies a net ring current signal as a current control signal to the ring oscillator 26. The net ring current signal shows a difference between an output current signal and a current dump output signal and corresponds to the difference between an output buffer trip point and a ring oscillator dummy means.;COPYRIGHT: (C)1993,JPO