Multiple Output LC Tank Varactor VCO with Ultra-Low Power Consumption and Low-Phase Noise

This paper presents the design of Varactor Tank Voltage Controlled Oscillator (VCO) with multiple outputs using Colpitts Oscillation. Design process followed industry guidelines in order to achieve ultralow power consumption and low phase noise production. Each VCO proposed is a combination of main tank, Colpitts Oscillator, Varactor tank, negative resistance and utilized with super filter voltage, impedance matching, synthesizer and buffer for VCOs combination purpose. This design is verified by measurement of output frequency ranged 806 MHz to 1054 MHz with 3V to 10.5V supply respectively for each VCOs. Whereas power consumption varies in the range of 335.407 mu W to 486.1814 mu W., The proposed VCO design shows significant improvements compared with earlier VCO design in terms of wider output operating frequency range, lower power consumption and better phase noise results.