pass band filter

Wim Verheyen catwim at innet.be
Thu Apr 3 19:51:57 CEST 1997


>Does anyone know how to calculate the values of Cs & Rs in this
>pass-band filter (attached) according to the required lowest and highest
>frequency ?

>From the IC Op-amp Cookbook :

Center frequency : Fc (for C1 = C2 = C)
                __________
       1       / R1 + R2
Fc = ------   / ---------
     2*pi*C \/   R1*R2*R3

Passband gain : H

         1
H = -------------
    (R1) (    C1)
    (--) (1 + --)
    (R3) (    C2)

Q : (Fh and Fl are high and low -3dB frequencies)

      Fc
Q = ------
    Fh -Fl

          Q
R1 = ------------
     H*2*pi*Fc*C1

                 Q
R2 = ------------------------
     (2*Q*Q - H) * 2*pi*Fc*C1

         Q
R3 = --------
     C1*pi*Fc

Hope this helps,
---------------------------------------------
 Wim Verheyen
 catwim at innet.be
 http://www.club.innet.be/~year0828/wim.html
 belkurz or kurzbel on undernet irc
---------------------------------------------




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