The INAx191 is a low bias current, 40-V common-mode, current-sensing amplifier with an enable pin. When disabled, the output goes to a high-impedance state, and the supply current draw is reduced to less than 0.1 µA per channel. The INAx191 is intended for use in either low-side and high-side current-sensing configurations where high accuracy and low current consumption are required. The INAx191 is a specially designed current-sensing amplifier, that accurately measure voltages developed across current-sensing resistors on common-mode voltages that far exceed the supply voltage. Current can be measured on input voltage rails as high as 40 V, with a supply voltage (VS) as low as 1.7 V.