SBOS470A December 2019 – June 2021 INA293
The INA293 is designed to measure current in a typical solenoid application. The INA293 measures current across the 50-mΩ shunt that is placed at the output of the half-bridge. The INA293 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 INA293 is connected to the analog-to-digital converter (ADC) of an MCU to digitize the current measurements.
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 INA293, with high bandwidth and slew rate, can be used to detect fast overcurrent conditions to prevent the solenoid damage from short-to-ground faults.