RL Filter Cutoff Calculator

Calculate the -3 dB cutoff frequency of an RL filter.

Ω
mH

Cutoff Frequency

15,915.5 Hz

Time Constant (L/R)0.0100 ms

Cutoff Frequency vs Resistance

RL Filter Cutoff

f_c = R / (2 x pi x L)

Time constant tau = L/R. An RL low-pass passes DC and attenuates high frequencies.

Example Calculation

R = 1k, L = 10 mH.

  1. 01L = 0.01 H
  2. 02f_c = 1000 / (2pi x 0.01) = 15,915.5 Hz
  3. 03tau = 0.01 / 1000 = 0.01 ms

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A complete guide to Ohm's Law. Learn the relationship between voltage, current, and resistance, with practical examples, the power triangle, and circuit analysis tips.

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