# Low Pass Sallen-Key filter has weird response in bode plot

I have the following circuit in Multisim and am getting the Bode plot at the bottom. Could someone please explain to me what is happening?

The AD8651 is listed as having a 50MHz bandwidth. Why is it that it goes astray at 17.4kHz?? I think it might be something wrong with my design but I am not quite experienced enough at this to narrow it down.

• can you post the file on gdrive and give the link – yogece Oct 29 '13 at 14:42
• – user1003131 Oct 29 '13 at 19:15

You need to add some DC bias to your input, so it idles at $\frac{Vpp-Vss}{2}$.