Colpitts Oscillator (Frequency)

The Frequency of a Colpitts Oscillator calculator compute the frequency of a Colpitts Oscillator (ƒ₀) based on the inductance and the capacitance of two capacitors.

INSTRUCTIONS: Choose units and enter the following:

• (L) Inductance
• (C1) Capacitance of the first capacitor
• (C2) Capacitance of the second capacitor

Oscillator Frequency (ƒ₀):  The calculator returns the frequency in hertz (Hz).  However, this can be automatically converted to compatible units via the pull-down menu.

The Math / Science

The Colpitts Oscillator Frequency equation is used to compute the frequency of oscillation i.e. approximately the resonant frequency of the LC circuit, which is the series combination of the two capacitors in parallel with the inductor.  The formula for the frequency of a Colpitts oscillator is:

           `ƒ_0 = 1 / (2*π*sqrt(L*(C1*C2)/(C1+C2) ) )`

where:

• ƒ₀ is the frequency of the Colpitts oscillator
• L is the Inductance
• C1 is the capacitance of the first capacitor
• C2 is the capacitance of the second capacitor

A Colpitts oscillator, invented in 1918 by American engineer Edwin H. Colpitts, is one of a number of designs for LC oscillators, electronic oscillators that use a combination of inductors (L) and capacitors (C) to produce an oscillation at a certain frequency. The distinguishing feature of the Colpitts oscillator is that the feedback for the active device is taken from a voltage divider made of two capacitors in series across the inductor.

Reference

Colpitts Oscillator . https://en.wikipedia.org/wiki/Colpitts_oscillator [Retrieved January 12, 2016]