It's connected to the output of an opamp through a series ~5k resistor, with a Schottky in parallel with the input to the ADC. The sequencing of the supply rails, -5V first, +5V second, causes the output of the opamp to become negative until the +5V comes up as much as ~500mS later. The resistor should limit the current to just under 1mA. We have not experienced any issues - this was brought up during a design review as an action item to clear with TI. Older ADCs had issues with negative inputs, so I understand why this was brought up.
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