A low-pass filter is an LC network designed to led frequencies under a certain value pass without attenuation and blocking frequencies above this value.
Figure shows the L, T and π configurations for those filters..
Formula 1
Where:
f is the cutoff frequency in hertz (Hz)
? = 3,14
L is the inductance in henrys (H)
C is the capacitance in farads (F)
Application Example:
Calculate the cutoff frequency of na LC low-pass filter formed by a 1 mH inductor in series with a 1,000uFcapacitor (L filter).
Data:
C = 1 000 µF = 10-3 F
L = 1 mH = 10-3 H
Fc = ?
Applying formula 1:
