Signal Processing & DSP

Intermediate

RC Filter Cutoff

Corner frequency of a simple RC low/high-pass filter.

Formula

f_c = \frac{1}{2\pi RC}

Variables

f_cCutoff (Hz)

RResistance (Ω)

CCapacitance (F)

Example

R=1kΩ, C=1µF: f_c ≈ 159 Hz

Did You Know?

At the cutoff frequency the signal is attenuated by 3 dB — half its power passes through.

dsp filter cutoff rc

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