## VCO Glossary

Active Components > VCO

**VCO Glossary**

**Voltage Controlled Oscillator (VCO): Type of oscillator that is continuously tunable by the application of a control voltage.**

**Frequency Tuning performance: The characteristic frequency vs. tuning voltage curve generated by a VCO when tuned from the minimum to the maximum tuning voltage extremes. Typically presented in a graph format as Frequency vs. Voltage.****Tuning Sensitivity or Modulation Sensitivity: The slope of the characteristic frequency tuning curve at a given tuning voltage (MHz/V).**

**Monotonic Tuning: Continuous positive or negative change in the frequency tuning curve.**

**Tuning Linearity: The amount of frequency deviation from a best fit straight line of the frequency vs. tuning voltage curve (MHz).**

**Output Power Variation: The variation of the output power of the fundamental frequency when observed over the specified frequency range into a 50 ohm load at a fixed temperature (dB).**

**Power Flatness: The variation of the output power from the average output power (dB).**

**Output Power Variation with Temperature: The variation of the output power with respect to a change in the device's temperature (dB/～C).****Frequency Drift with Temperature: The variation of the output frequency with respect to a change in the devices temperature (MHz/～C).****Spurious Output (Non-Harmonic): Unwanted frequencies not harmonically related to the fundamental frequency (dBc).****Harmonic Suppression: The level of harmonics (nfo) relative to the level of the fundamental frequency (dBc).**

**Frequency Pushing: The variation of the output frequency due to a change in the supply voltage (MHz/V).****Frequency Pulling: The variation of the output frequency due to a change in the output load conditions. Typically specified into a 12 dB Return Loss (MHz).****3 dB Modulation Bandwidth: The modulating frequency at which the frequency deviation decreases to 0.707 of its DC value. This is also a function of the modulating source impedance, which is typically 50 ohms.****Phase Noise: The single side band phase noise in a 1 Hz bandwidth, measured relative to the carrier level at a specified offset frequency (dBc/Hz).****VCO Input Capacitance: The total equivalent input capacitance seen at the tuning port of the VCO (pF).****Microphonic: Spurious signals seen on the VCO output when the device is subjected to vibration or shock.****Frequency Drop Outs: The sudden unexpected loss of frequency output while tuning across the frequency range.**