Accurate, Low-Cost Current Monitor Housed In Mini Package

Serving up a wide input common-mode voltage range, low quiescent current, and a tiny, space-saving SOT-23 package, the INA138 low-cost current shunt monitor is targeted for use in computers, telephones, automobiles, and a variety of other products. In performing as a high-side current shunt monitor, the device converts a differential input voltage to a current output, which is then converted back to a voltage with an external load resistor for setting gain from 1 to >100.
The unipolar, high-side INA138 draws only 25 µA of quiescent current, permitting shunt measurements to be made with minimal error. Input common-mode and power supply voltages are independent and can range from 2.7V to 3 6V. The IC costs $0.95 each/1000.