1 Features

• Precision design with integrated shunt resistor

– ±75A continuous current at 25°C

– ±50A continuous current at +125°C

– Shunt resistor: 400μΩ

– Shunt inductance: 2nH

• Wide common-mode voltage range: –4V to +110V

• Enhanced PWM rejection optimized for systems

subject to switching common-mode voltages

– Supports switching frequencies up to 125kHz

• Excellent CMRR

– 160dB DC CMRR

– 114dB AC CMRR at 50kHz

• High measurement accuracy

– System Gain error (maximum)

• Version A: ±0.35%, ±35ppm/°C drift

• Version B: ±1%, ±100ppm/°C drift

– Offset current (maximum)

• Version A: ±40mA, ±70mA over temperature

• Version B: ±210mA, ±250mA over

temperature

• Adjustable gain with external resistor divider

network: 20mV/A to 400mV/A

• Open-drain temperature alert at TJ of 160°C

2 Applications

• Motor drives

• Solenoids and actuators

• Injection molding machine

• Cordless power tools

• Medical cordless tools

• Drone propeller speed control

3 Description

The INA790x is a voltage output, current sense

amplifier with an integrated shunt resistor of 400μΩ.

The INA790x is designed to monitor bidirectional

current over a common-mode range of –4V to 110V,

independent of the supply voltage. Adjustable gain

option assists in optimizing the system dynamic

range. The integration of the Kelvin connected shunt

resistor with a zero-drift chopped amplifier provides

calibration equivalent measurement accuracy, ultralow

temperature drift performance of ±35ppm/°C, and

an optimized layout for the sensing resistor.

The INA790x is designed with enhanced PWM

rejection circuitry to suppress disturbance from large

(dv/dt) common-mode transients and enable realtime

continuous current measurements in switching

systems. The continuous measurements are critical

for inline current measurements in a motor-drive

application, and for solenoid valve control application.

This device operates from a single 2.7V to 5.5V power

supply, drawing a maximum of 4.25mA of supply

current. All versions are specified over the extended

operating temperature range (–40°C to +125°C), and

are available in a 15-pin VQFN package.