Communication ICs
FAttached components
BA4116FV
FDetermining the filter amplifier constant (multi-layer recovery band pass filter)
f0: Center frequency
Q: Center frequency f0 / band width BW
A0: I / O gain
The reference resistance R0 is determined as C1 = C2 =
C0.
R0 = 1 / 2πf0 S C0
R1 = R0 S Q / A0
R2 = R0 / [2Q - (A0 / Q)]
R3 = 2R0 S Q
FElectrical characteristic curves
The Filter gain can be adjusted by varying R1, but with the
A0 > 1 design, please be aware that influence from the
open loop characteristic of the amplifier causes offset in
the center frequency f0.
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