SLVSFV1B August 2018 – August 2021 DRV8350F , DRV8353F
PRODUCTION DATA
The goal of this example is to set the VDS monitor to trip at a current greater than 75 A. According to the CSD19535KCS 100 V N-Channel NexFET™ Power MOSFET data sheet, the RDS(on) value is 2.2 times higher at 175°C, and the maximum RDS(on) value at a VGS of 10 V is 3.6 mΩ at TA = 25°C. From these values, the approximate worst-case value of RDS(on) is 2.2 × 3.6 mΩ = 7.92 mΩ.
Using Equation 13 with a value of 7.92 mΩ for RDS(on) and a worst-case motor current of 75 A, Equation 14 shows the calculated desired value of the VDS overcurrent monitors.
For this example, the value of VDS_OCP was selected as 0.6 V.
The SPI devices allow for adjustment of the deglitch time for the VDS overcurrent monitor. The deglitch time can be set to 1 µs, 2 µs, 4 µs, or 8 µs.