8.3.4 Low-Side Current Sense Amplifiers (DRV8323 and DRV8323R Only)

The DRV8323 and DRV8323R integrate three, high-performance low-side current sense amplifiers for current measurements using low-side shunt resistors in the external half-bridges. Low-side current measurements are commonly used to implement overcurrent protection, external torque control, or brushless DC commutation with the external controller. All three amplifiers can be used to sense the current in each of the half-bridge legs or one amplifier can be used to sense the sum of the half-bridge legs. The current sense amplifiers include features such as programmable gain, offset calibration, unidirectional and bidirectional support, and a voltage reference pin (VREF). If any of the three current sense amplifiers are not being used, they can be tied off by shorting the SNx pin to the SPx pin and leaving the SOx pin unconnected. Remember to connect the SPx or SNx pin to the low-side FET source, so that the overcurrent VDS monitor is still functional