Coaxial Resonators for Voltage-Controlled Oscillator (VCO) Applications

Many engineers choose to design their own Voltage-Controlled Oscillator (VCO) circuits to reduce cost, size, and power consumption. Development of high Quadrature (Q) ceramic coaxial resonators simplifies the VCO design process. When a Skyworks coaxial resonator (transmission line) is the frequency determining element of a VCO, it typically replaces a discrete inductor.

The rugged ceramic resonator has enormous benefits over traditional coils by offering better temperature stability, higher Q, and no microphonics.

This Application Note introduces the design of the Skyworks coaxial resonators, outlines their use in a VCO, and details the method of selecting the correct part.