JAJSF51A April 2018 – July 2018 DRV8306
PRODUCTION DATA.
The goal of this example is to set the VDS monitor to trip at a current greater than 50 A. According to the CSD18514Q5A 40 V N-Channel NexFET™ Power MOSFET data sheet, the RDS(on) value is 1.8 times higher at 175°C, and the maximum RDS(on) value at a VGS of 10 V is 4.9 mΩ. From these values, the approximate worst-case value of RDS(on) is 1.8 × 4.9 mΩ = 8.82 mΩ.
Using Equation 10 with a value of 8.82 mΩ for RDS(on) and a worst-case motor current of 50 A, Equation 11 shows the calculated the value of the VDS monitors.
For this example, the value of VDS_OCP was selected as 0.51 V.
The deglitch time for the VDS overcurrent monitor is fixed at 4 µs.