Design of Low-Power Differential CMOS LC Voltage Controlled Oscillator using Genetic Algorithm

A new configuration of differential CMOS LC voltage controlled oscillator (VCO) is presented and analyzed in this work. The proposed circuit is a complementary LC-VCO which is adopted from the gate-to-source capacitive feedback Colpitts VCO. The proposed VCO has the advantage of large value of negative conductance which results in a more reliable startup oscillation at the lower current. Also, the design approach makes to employ only one inductor in the resonator which saves the chip area. Genetic Algorithm (GA) is used to determine the value of parameters for the proposed VCO in order to improve the circuit performance. The proposed VCO has been designed to oscillate at the frequency of2.75 GHz with 1.1 V supply voltage.