The INA280 measures the differential voltage developed by current flowing through a resistor that is commonly referred to as a current-sensing resistor or a current-shunt resistor. The INA280 operates in unidirectional mode only, meaning it only senses current sourced from a power supply to a system load as shown in Figure 7-3.

Figure 7-3 Unidirectional Application

The linear range of the output stage is limited to how close the output voltage can approach ground under zero-input conditions. The zero current output voltage of the INA280 is very small, with a maximum of GND + 25 mV. Make sure to apply a sense voltage of (25 mV / Gain) or greater to keep the INA280 output in the linear region of operation.