Sallen-key and Chebyshev filter

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Homework Statement

I have a transfer function from a second order chebyshev filter and the general transfer function of a sallen-key circuit. I have some questions.

Homework Equations

I am using a 2nd order low-pass filter sallen key on page 8 of this pdf :http://focus.ti.com.cn/cn/lit/an/sloa024b/sloa024b.pdf

My R1 and R2 are the same and I have only one value of C1 and C2.

For the Sallen-key I know the tranfer function is

$$H \left( s \right) = \frac{k w^{2}}{ s^{2} + \frac{w}{Q}s + w^2}$$

For a chebyshev filter I have a second order transfer function as follows $$H \left( s \right) = \frac{1}{ s^{2} + 0.1705s + 0.903}$$

I know that $K = 3 - \frac{1}{Q}$

K is my Gain.

$$k = 1+ \frac{R_{b}}{R_{a}}$$

The Attempt at a Solution

My problem is that if I use the equation $K = 3 - \frac{1}{Q}$ I get a different value for K than if I use the equation $k = \frac{1}{w^2}$

I got the equation $k = \frac{1}{w^2}$ from inspecting the transfor function of the Sallen-Key and noticing that [itex] kw^{2} = 1[/tex] for the chebyshev TF.

Apparently, the equation is not correct but I don't know why. I would like someone to shed more light on this.

 

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Also, I am not sure if the value of Q that I am using for the Chebyshev transfer function is the same as the value of Q that I am using for the Sallen-Key transfer function.