The INA310x is designed to measure current in a typical solenoid application. The INA310x measures current across the 50-mΩ shunt that is placed at the output of the half-bridge. The INA310x measures the differential voltage across the shunt resistor, and the signal is internally amplified with a gain of 50 V/V. The output of the INA310x is connected to the analog-to-digital converter (ADC) of an MCU to digitize the current measurements.

R₂ is fixed as 10 kΩ to avoid loading of OUT as recommended in Overcurrent Threshold Connection. R₁ is calculated as 69.15 kΩ using Equation 1.

R₁ (69.15 kΩ) and R₂ (10 kΩ) divides down the output which is an input to the comparator. This sets the overcurrent alert threshold of 1.9 A.

Solenoid loads are highly inductive and are often prone to failure. Solenoids are often used for position control, precise fluid control, and fluid regulation. Measuring real-time current on the solenoid continuously can indicate premature failure of the solenoid, which can lead to a faulty control loop in the system. Measuring high-side current also indicates if there are any ground faults on the solenoid or the FETs that can be damaged in an application. The INA310x, with high bandwidth and slew rate, can be used to detect fast overcurrent conditions to prevent the solenoid damage from short-to-ground faults.