DESIGN OF VCO USING CURRENT MODE LOGIC WITH LOW SUPPLY SENSITIVITY

Krishnaveni.S, Bibin Sam Paul.S

Abstract: The function of an oscillator is to convert dc energy into RF. Voltage Controlled Oscillator (VCO) is a type of oscillator whose output frequency can be varied by a control voltage. Here the VCO is designed using 0.18µm CMOS-RF technology using current mode logic. The Current mode logic is the fastest logic and is mainly used in Clock and Data Recovery applications. Current mode logic (CML) is a differential logic and provides noise immunity. Using the proposed design the current mode logic VCO operates with a supply voltage of 1.8 V and frequency varies from 2 MHz to 2.5 MHz. Its normalized supply sensitivity is 0.976 and optimum sensitivity is 0.966.

Keywords: VCO, Supply sensitivity, CML, Ring oscillator

DOI: https://doi.org/10.15623/ijret.2014.0302092