Voltage-controlled oscillator

A voltage-controlled oscillator (VCO) is an electronic oscillator whose oscillation frequency is controlled by a voltage input. The applied input voltage determines the instantaneous oscillation frequency. Consequently, a VCO can be used for frequency modulation (FM) or phase modulation (PM) by applying a modulating signal to the control input. A VCO is also an integral part of a phase-locked loop. VCOs are used in synthesizers to generate a waveform whose pitch can be adjusted by a voltage determined by a musical keyboard or other input.

A voltage-to-frequency converter (VFC) is a special type of VCO designed to be very linear in frequency control over a wide range of input control voltages.^[1]^[2]^[3]

^ Godse, Atul P.; Bakshi, U. A. (2009). Linear Integrated Circuits And Applications. Technical Publications. p. 497. ISBN 978-8189411305.
^ Drosg, Manfred; Steurer, Michael Morten (2014). Dealing with Electronics. Walter de Gruyter GmbH. pp. 4.5.3. ISBN 978-3110385625.
^ Salivahanan, S. (2008). Linear Integrated Circuits. Tata McGraw-Hill Education. p. 515. ISBN 978-0070648180.

[Godse-1] Godse, Atul P.; Bakshi, U. A. (2009). Linear Integrated Circuits And Applications. Technical Publications. p. 497. ISBN 978-8189411305.

[Drosg-2] Drosg, Manfred; Steurer, Michael Morten (2014). Dealing with Electronics. Walter de Gruyter GmbH. pp. 4.5.3. ISBN 978-3110385625.

[Salivahanan-3] Salivahanan, S. (2008). Linear Integrated Circuits. Tata McGraw-Hill Education. p. 515. ISBN 978-0070648180.

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