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INA823: Input behaviour when unpowered

Part Number: INA823
Other Parts Discussed in Thread: INA826S

Tool/software:

I would like to use INA823 to monitor the voltage of an attached battery.
If the whole circuit is powered off, the connection to the battery is still there and therefore the circuit sees 0V at -IN and 3.7V at +IN,
which usually causes some current from +IN to V+ to sort of back-power the whole circuit, which I need to prevent,
but the main question therefore is: are those overvoltage FETs turned off and therefore prevent a current flow (if within ±5V) at +IN and -IN when the circuit is powered off?
I attached a picture of how the external and internal circuit roughly looks like:

Commented datasheet circuit

  • There is no switch that disconnects the inputs.

    To prevent this current flow, use a device with shutdown like the INA826S and keep it powered. Alternatively, put a switch in front of the INA.

  • Adding to Clemens' answer, the overvoltage protection FETs are effectively a voltage controlled resistors that limit the current to around +/-4mA when the inputs are driven above or below INA823 rails (supplies).