High linearity voltage-controlled oscillator

A linearization technique for CMOS voltage-controlled oscillators (VCOs) is presented. The linearity of the oscillator is improved by applying a feedback loop using a switched-capacitor network as a frequency-to-voltage converter (FVC). The technique is verified by circuit-level simulation using parameters of a 0.35-µm CMOS technology. After the linearization, the linearity error of VCO can be improved to less than 0.015% for a dynamic range of 60 dB.