I want to measure the AC Current flowing through a Piezocrystal (replaced in the circuit with a resistor) being driven by a TI DRV2700. http://www.ti.com/lit/ds/symlink/drv2700.pdf This Chip puts out a differential 200Vpp and so ive decided to power it from a standard wall adapter, while the analog frontend and the AD Converter get their Power from a USB Port. The circuit reflects my understanding of the System. Is it true that with frequencys of 1khz to 10khz the Isolation capacitance will produce an error current? If so, how can i prevent this problem?

Thanks everyone! What i think is going on

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    \$\begingroup\$ Why are you not using the equivalent circuit of your piezo crystal. Replacing it with a 100 Mohm resistor is arbitrary and completely misses the point. \$\endgroup\$ – Andy aka Mar 25 '20 at 15:10
  • \$\begingroup\$ Thanks for your Comment! The 100Meg Resistor is supposed to be the isolation resistance of the wall adapter. Ive used a 100k Resistor R2 in place of the piezo to simplify current calculation while testing. \$\endgroup\$ – dinocroc123 Mar 25 '20 at 17:27

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