I am using the operational amplifier AD745 in a charge amplifier configuration for amplifying piezoelectric sensor signals. In the datasheet it says that the operational amplifiers voltage noise increases with decreasing source capacitance. I am interested in the behaviour of the current noise which might also change with the source capacitance...? Does anybody have an idea how to measure the operational amplifiers voltage and current noise in dependence of the input capacitance and also frequency-dependent?
Thank you very much in advance!