8.4.2 Accuracy Variations as a Result of V_SENSE and Common-Mode Voltage

The accuracy of the INA270 and INA271 current shunt monitors is a function of two main variables: V_SENSE (V_IN+ – V_IN–) and common-mode voltage (V_CM) relative to the supply voltage, V_S. V_CM is expressed as (V_IN+ + V_IN–) / 2; however, in practice, V_CM is used as the voltage at V_IN+ because the voltage drop across V_SENSE is usually small.

This section addresses the accuracy of these specific operating regions:

Normal Case 1: V_SENSE ≥ 20 mV, V_CM ≥ V_S

Normal Case 2: V_SENSE ≥ 20 mV, V_CM< V_S

Low V_SENSE Case 1:

V_SENSE< 20 mV, –16 V ≤ V_CM< 0

Low V_SENSE Case 2:

V_SENSE< 20 mV, 0 V ≤ V_CM ≤ V_S

Low V_SENSE Case 3:

V_SENSE< 20 mV, V_S< V_CM ≤ 80 V