Current sense amplifiers created for cost-optimised applications

The Texas Instruments INA181, INA2181, and INA4181 current sense amplifiers are created for cost-optimised applications. They are part of a family of bidirectional, current-sense amplifiers (also called current-shunt monitors) that sense voltage drops over current-sense resistors at common-mode voltages from –0.2V to +26V, separate from the supply voltage. The family integrates a matched resistor gain network in four, fixed-gain device options: 20V/V, 50V/V, 100V/V, or 200V/V. This matched gain resistor network lessens gain error and reduces the temperature drift. These amplifiers operate from a single 2.7V to 5.5V power supply. The single-channel INA181 draws a maximum supply current of 260µA; whereas, the dual-channel INA2181 draws a maximum supply current of 450µA, and the quad-channel INA4181 draws a maximum supply current of 900µA. The INA181 is available in a six-pin, SOT-23 package, the INA2181 in a 10-pin VSSOP package, and the INA4181 in a 20-pin TSSOP package. All are specified over an extended operating temperature range of –40C to +125C.