Understanding Voltage-Controlled Oscillators

Voltage-controlled oscillators (VCO) are oscillators whose output frequency is controlled by an external tuning voltage, and they are used in electronic and RF applications. Different VCO design approaches yield different parameters and performance, and therefore it is important to measure or characterize VCOs under different voltage and load conditions. This white paper provides a short technical introduction to voltage-controlled oscillators and explains the most common and the most important measurements made during the VCO characterization process.