Adjusting the gain on a 4th Order Butterworth Bandpass fIlter gain
It's more complicated than that.  The resistors &amp; capacitors more or less set the gain and filter characteristics simultaneously.  The easiest thing to do would be to go back to the TI tool and enter in your new numbers.

To solve the problem of your ADC range being from 0-3.3V, you can use a "pseudo-ground" that's right in the middle of your ADC range (I'm assuming 1.75V).  There are a lot of ways to skin this cat -- in your case, a simple RC circuit should do, as pictured below.  There's an almost endless number of fancier ways, but if your circuit's going to be always on, and you don't care about a bit of DC bias in the signal going into your signal processing, this should be OK.







simulate this circuit &ndash; Schematic created using CircuitLab