What Is Voltage Controlled Oscillator

Voltage controlled oscillator v f curve with discontinuity this curve shows a small dip and would result in the phase locked loop becoming unstable.

What is voltage controlled oscillator. A voltage controlled oscillator is an oscillator with an output signal whose output can be varied over a range which is controlled by the input dc voltage. Voltage controlled oscillator vco from the name itself it is clear that the output instantaneous frequency of the oscillator is controlled by the input voltage it is a kind of oscillator which can produce output signal frequency over a large range few hertz hundreds of giga hertz depending on the input dc voltage given to it. The output frequency of the voltage controlled oscillator is either sinusoidal or sawtooth. The applied input voltage determines the instantaneous oscillation frequency.

A voltage controlled oscillator is a widely used electronic oscillator where the input tuning voltage determines the oscillation frequency. Vco is an acronym for voltage controlled oscillator. For now you can imagine a voltage controlled oscillator vco to be a black box which takes in voltage of variable magnitude and produces. A vco is also an integral part of a phase locked.

A voltage controlled oscillator vco is an electronic oscillator whose oscillation frequency is controlled by a voltage input. Voltage controlled oscillators are important components in many applications such. The phase noise performance of the voltage controlled oscillator is of particular importance in some pll applications particularly where they are used in frequency. The frequency of this waveform is varied by varying the magnitude of the input voltage.

Consequently a vco can be used for frequency modulation fm or phase modulation pm by applying a modulating signal to the control input. It is a device that produces such an oscillating output signal whose frequency can be regulated or altered by the input dc voltage. A lm566 is a voltage controlled oscillator ic unit which is built with internal circuitry to generate both triangular and square wave signals whose frequency is set or adjusted by external capacitor and resistor followed with an application of dc voltage. In other words we can say vco generates an output signal having an adjustable frequency range that is controlled by the dc input voltage.

The oscillation frequency varies from few hertz to hundreds of ghz. The simplest and most common control input is a dc potential derived from a special musical keyboard which acts rather like a complicated switched potentiometer with each key closing a switch on a continuous resistive element.