A Voltage Controlled Oscillator, or VCO, is an electronic component that generates a periodic oscillating signal whose frequency can be adjusted by varying the voltage input. The main function of a VCO is to provide a controllable frequency source that can be used in a multitude of applications. They are fundamental components in systems that require signal modulation, such as in radio transmitters, phase-locked loops, and frequency synthesizers. VCOs are valued for their ability to adjust frequencies on the fly, making them essential in telecommunications, broadcasting, and electronic music.
The main uses of VCOs span a range of technologies, often seen in RF (radio frequency) communication systems, where precise frequency control is vital. Characteristics such as high-frequency stability, low phase noise, and a wide tuning range define the efficiency and performance of the VCOs. They also differ in the type of output wave they generate, for example, some may produce a sine wave while others a square wave, catering to specific application requirements. Notable manufacturers of VCOs include Analog Devices Inc., Texas Instruments, and Mini-Circuits, each offering a variety of models to suit different functional needs of electronic devices.