Unidirectional operation allows the INA28x-Q1 to measure currents through a resistive shunt in one direction. In the case of unidirectional operation, the output could be set at the negative rail (near ground, and the most common connection) or at the positive rail (near V+) when the differential input is 0V. The output moves to the opposite rail when a correct polarity differential input voltage is applied.

The required polarity of the differential input depends on the output voltage setting. If the output is set at the positive rail, the input polarity must be negative to move the output down. If the output is set at ground, the polarity is positive to move the output up.

The following sections describe how to configure the output for unidirectional operation.