Design of Ring Oscillator based VCO with Improved Performance

Abstract

Voltage Controlled Oscillator plays significant role in communication system design. The design of Voltage Controlled Oscillator (VCO) with low power consumption and high frequency range is presented in this paper. The VCO is based on a single ended CMOS inverter ring oscillator. Accurate frequency of oscillation in Ring Oscillator is an important design issue. A Voltage Controlled Ring Oscillator with wide tuning range from 917.43MHz to 4189.53MHz can be achieved using bulk driven technique by varying the threshold voltage of the MOS circuits. The circuit is designed using 0.13µm CMOS process for a supply voltage of 1V. Simulation results show better accuracy compared to existing current staved ring VCO using different number of inverter stages.

Keywords: Bulk driven technique, CMOS Process, Ring Oscillator, Voltage Controlled Ring Oscillator, Inverter.