Tool/software:
I'm using AD8226ARMZ-R7 from Analog devices with a gain of 1.99. The output of this Op-Amp is fed to a 6 pole 3KHz Butterworth anti-alising low pass filter having a unity gain formed by using OPA2322AIDGKR. I wanted to see the frequency response of this filter circuit by altering the values of the 1st stage RC components. I tried webench.ti.com/.../filter-response but it doesn't let me choose the current part i'm using. Does anyone have any idea on the back-end calculations that generate the frequency roll of curve ?