If the differential input voltage (VIN+ – VIN–) times gain exceeds the voltage swing specification, the INAx181 drive the output as close as possible to the positive supply or ground, and does not provide accurate measurement of the differential input voltage. If this input overload occurs during normal circuit operation, then reduce the value of the shunt resistor or use a lower-gain version with the chosen sense resistor to avoid this mode of operation. If a differential overload occurs in a fault event, then the output of the INAx181 returns to the expected value approximately 20 µs after the fault condition is removed.
When the INAx181 output is driven to either the supply rail or ground, increasing the differential input voltage does not damage the device as long as the absolute maximum ratings are not violated. Following these guidelines, the INAx181 output maintains polarity, and does not suffer from phase reversal.