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AD8138S and output protection diodes

In our instrument we use AD8138S in configuration as depicted below. Unit A is separated from Unit B and the AD8138S are powered from separate power supplies VP_A, VN_A (unit A) and VP_B, VN_B (unit B). The analogue signal is transmitter over the harness between units.

In certain modes only Unit B is powered. The power supplies at the Unit A are in that modes VP_A=0, VN_A=0. We want to shut down part of the analogue signal chain.

In such a case an VCM voltage will appear at the input of the Unit B. An since there is a connection between those units this voltage will be present on the outputs of the unpowered AD8138 in the unit A.

My question is: is it OK for the AD8138 to apply such a signal to outpus of unpowered component? Rg=499, Rf=1k.

Kind regards,

F.