Amplifier ICs

INA240A1QPWRQ1

INA240A1QPWRQ1 - 20V/V Current Sense Amp AEC-Q100 | Texas Instruments

The Texas Instruments INA240A1QPWRQ1 is an AEC-Q100 qualified, voltage-output current sense amplifier with a fixed gain of 20 V/V (A1 version), delivered in an 8-pin TSSOP (PW) package rated from -40C to +125C. It senses voltage drops across shunt resistors over an exceptionally wide common-mode voltage range of -4V to 80V, independent of the 2.7V to 5.5V supply voltage. A current sense amplifier is a specialized difference amplifier optimized to accurately measure small shunt voltages riding on high common-mode potentials. Within the power-management IC hierarchy, it sits between the shunt resistor and an ADC or controller, converting current into a ground-referenced analog voltage. Current sensing is fundamental to motor control, battery management, and overcurrent protection in automotive and industrial systems. Key features include ultra-precise zero-drift architecture with very low offset and drift, a bidirectional output configurable via REF1 and REF2 pins, and enhanced PWM rejection. The enhanced PWM rejection is the defining differentiator: it suppresses large common-mode transients common in PWM-driven inverter stages, where conventional current sense amplifiers saturate and corrupt the measurement for several microseconds after each switching edge. The device provides reference pins to configure operation as either unidirectional or bidirectional output swing. The negative common-mode capability down to -4V allows operation below ground, accommodating the flyback period of typical solenoid and motor drive applications. The zero-drift topology delivers DC accuracy suitable for precision torque control and coulomb counting without periodic calibration. Typical applications include in-line motor phase current sensing in HEV/EV traction inverters, solenoid current monitoring, battery current monitoring in 12V and 48V systems, and DC bus current sensing in servo drives and solar inverters. Design tip: keep shunt resistor power dissipation in check by choosing the lowest gain version (20 V/V for the A1) that meets your ADC input range, and place the INA240 close to the shunt with tight, symmetric Kelvin routing to INP and INN to preserve the enhanced PWM rejection performance.