I am currently working on the design of a 2nd order wien bridge notch filter whose general circuit is shown in the attached file. I derived the transfer function to be:
H(s)=-[(R/(3R-3))(s^2+(1/RC)^2)]/[s^2+(3/RC)s+(1/RC)^2}
from this I could deduce that my passband gain is -R/(3R-3)
and also that 2∏f=(1/RC)
However, I am tempted to think that my rejection quality,Q, is = (RC/3) from the term in s in the denominator but I doubt if my assumptions are correct.
If anyone can confirm this, I would be very grateful. I was could not find anything on the internet which talked about a formula for rejection quality,Q, for a wien bridge notch filter though a lot of websites promised that it was simple to make
H(s)=-[(R/(3R-3))(s^2+(1/RC)^2)]/[s^2+(3/RC)s+(1/RC)^2}
from this I could deduce that my passband gain is -R/(3R-3)
and also that 2∏f=(1/RC)
However, I am tempted to think that my rejection quality,Q, is = (RC/3) from the term in s in the denominator but I doubt if my assumptions are correct.
If anyone can confirm this, I would be very grateful. I was could not find anything on the internet which talked about a formula for rejection quality,Q, for a wien bridge notch filter though a lot of websites promised that it was simple to make
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