Calculation component values of passive CLC (lowpass) filters.








General lowpass filter setup:



Standard filter types:

Approximation "a" "b" "c" Remarks
Critical 0.13249702 0.77974306 1.5295 Best impulsrespons
Bessel 1/15 2/5 1 fk on max flat groupdelay
Bessel modified 0.36077727 1.232954186 1.755672368 fk on -3 dB
Butterworth 1 2 2 Max flat amplitude response
Chebyshev 0.1 1.6332 2.2734 2.2279 Ripple 0.1 dB
Chebyshev 0.5 2.2235 2.3862 2.5038 Ripple 0.5 dB
Chebyshev 1 2.6713 2.4114 2.7598 Ripple 1 dB
Chebyshev 2 3.3694 2.4073 3.2294 Ripple 2 dB
Chebyshev 3 3.9937 2.3844 3.7055 Ripple 3 dB

Where a,b and c correspond to


Input parameters:

"a": "b": "c":
Non-ideal coil: L: H Rcu: Ohm
Capacitor C2: C2: F
Cut-off frequency: fk: Hz





Output results for D<0: D: {"casus irreducibilis"}
Rs: Ohm C1: F Rl: Ohm H(0):
Rs: Ohm C1: F Rl: Ohm H(0):
Rs: Ohm C1: F Rl: Ohm H(0):
Output result for D>0:
Rs: Ohm C1: F Rl: Ohm H(0):
Output results for D=0: {unlikely to occur}
Rs: Ohm C1: F Rl: Ohm H(0):
Rs: Ohm C1: F Rl: Ohm H(0):

...for non-commercial use only...


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