Hi,
We would like to model the impact of the AIC3254's input impedance on the signal generated by a high impedance source (piezo unimorph disc). We are only really interested in the frequency response between around 1KHz and 10KHz, however would like the AIC3254 amplified and digitized signal to be as distortion free as possible for signals containing the above frequencies.
We are using TINA-TI to model the piezo element, and are trying to emulate the input of the AIC3254 using an instrumentation amplifier (INA121, or INA827) as a differential amplifier, with 40k ohm bias resistors between both the inverting and non-inverting inputs to the common rail (aka ground when using +/- supply rails). Will such a configuration give us a reasonable approximation of what we would expect from the AIC3254 when configured in differential mode with 40K ohm input impedances?
Kind regards,
Sam
