LC Oscillator


There are fully charged capacitors.
What happens if the capacitor draws current into the inductor?
What is the similarity between physical vibration and electrical vibration?

LC oscillator

An LC circuit(also called a resonant circuit) is an electric circuit consisting of an inductor and a capacitor.
The circuit can act as an electrical resonator, an electrical analog of a tuning fork, storing energy oscillating at the circuit's resonant frequency.

Find resonant frequency of LC oscillator

The resonant frequency of the LC vibration circuit is determined when the capacitor's reactance and the reactance of the inductor are the same.

\[ X_L = X_C \]
\[ 2 \pi fL = \frac{1}{2 \pi fC} \]

f: frequency (Hz)
L: Inductance of a Inductor(H)
C: Capacitance of a capacitor (F)

Resonant frequency is

\[ f = \frac{1}{2 \pi \sqrt{LC}} \]

The method of selecting the current of the desired frequency using the LC circuit is widely used in radio and wireless communication circuits.