LC Band-Pass
Series LC values
f₀ = 1/(2π√LC), Q = R√(C/L), BW = R/L. Enter L, C and R.
Band-pass response
How to use this calculator
A series LC circuit with a resistance forms a band‑pass filter. The resonant frequency is f₀ = 1 / (2π√(LC)), the quality factor Q = R·√(C/L), and the bandwidth BW = R/L. Enter L, C and R and the tool returns f₀, Q, BW and the two −3 dB frequencies f₁ and f₂. A higher R (lower Q) gives a wider, flatter passband; a lower R (higher Q) gives a narrower, sharper one.
What it means in a real circuit
LC band‑passes are used to select a frequency band from a mixture of signals — radio tuning, notch removal, and matching. The series resonance at f₀ presents minimum impedance, so current (and thus the output across R) peaks there. In practice, the inductor's DC resistance and the source/load impedances set the real Q, so this ideal calculation is your design target, to be confirmed in simulation.