When the voltage on pin SENSE exceeds V_TRIP (0.5 V), overcurrent is detected. The R_SENSE resistor should be sized to set the desired I_TRIP level.

To set I_TRIP to 2.5 A, R_SENSE = 0.5 V / 2.5 A = 0.2 Ω.

To prevent false trips, I_TRIP must be higher than regular operating current. Motor current during startup is typically much higher than steady-state spinning, because the initial load torque is higher, and the absence of back-EMF causes a higher voltage and extra current across the motor windings.

It is beneficial to limit startup current by using series inductors on the DRV8801-Q1 output, as that allows I_TRIP to be lower, and it may decrease the system’s required bulk capacitance. Startup current can also be limited by ramping the forward drive duty cycle.