Design of A Low-Supply Sensitivity LC VCO with Complementary Varactors

摘要

Analysis of the effect of supply-induced frequency variation on the LC VCO is described. According to the results of the analysis, the first-order impact on the supply sensitivity is that the varactor's effective capacitance varies with the supply voltage. A novel compensation technique based on complementary varactors to reduce the supply sensitivity of the LC VCO is proposed with no extra power dissipation, nor phase noise degradation. Simulation results show that this compensation technique reduces the periodic jitter by more than 93%.