I would like to use AD9102 as a self-test signal generator to a low noise sensor signal conditioning path.
The sensor is a capacitive sensor, approximately 1.7nF. The frequency range is 10kHz to 200kHz, thus the sensor impedance varies roughly from 9.36kOhm to 468ohm.
I have a low noise amplifier, non-inverting, bipolar rail connected directly to sensor. However, I would like to be able to either disconnect the sensor and inject a voltage signal from AD9102 to the low noise amplifier (signal conditioning + ADC self-test) or keep the sensor connected to LNA and use AD9102 to inject a known current signal into the sensor (basically implementing an impedance analyzer).
My question is this: does anyone have any recommendations on how to best accomplish this analog interface? I am looking for extremely low additive noise analog switches (LNA runs from +-3.3V rails), and how to arrange signal conditioning between AD9102 for both voltage injection into LNA and current injection into the sensor.