Second order active low pass filter values

Question

I want to use a second order active low pass filter to cut off frequencies over 33kHz . The input is 1.3 Volts peak to peak sine wave of 32 Khz and I want to make it 30kHz of 1Vpp . The formulas for calculating the values on the components of S.O.A.L.P. are for different SOALP than mine . Can someone provide me with the formulas that I need to calculate the values of my schematic or better provide the values and explain

Edit: the op amp is provided 20V in the [+] wire and is grounded on the [-] wire

Edit 2: the formulas I found for other SOALP are on this link http://www.electronics-tutorials.ws/filter/second-order-filters.html

Answer 1

There are better steps to design a filter of this type;

Define specs then choose the type of knee response.. Low Q like Bessel give flat group delay or rate of change of phase shift. Higher Q with steeper edge like Chebychev compromise group delay but steeper edge and some ripple in passband. Others include Butterworth, etc.

Filter specs

1. Choose Type & order (2, 4, 6, 8 ...) (low cost and much better performance)
   or choose characteristics ( better)

   • Pass band gain
   • Pass Band bandwidth -3dB f
   • Pass Band Ripple

   • Reject Band __ dB at f

   • then use www.ti.com active filter tool to design AC part , then do more to correct DC bias part.

   • it only takes minutes to create an email login, validate, then use the tool http://www.ti.com/design-tools/signal-chain-design/webench-filters.html

2. Ensure DC bias is in valid CM range by adding biasing, e.g. Vcc/2 instead of Gnd.

3. Scale R up and C down to minimize current
4. Check input bias current offset voltage and balance both input R equiv with suitable R's. on (+) input.