The chopping current is set based on the sense resistor value and the analog voltage at the VREF pin. Use Equation 11 to calculate the current (I(CHOP)). The amplifier gain, AV, is 19.8 V/V for the DRV8702D-Q1 and VIO is typically 5 mV (input referred).
For example, if the desired chopping current is 15 A, select a value of 10 mΩ for R(SENSE). The value of VVREF must therefore be 2.975 V. Add a resistor divider from the AVDD (5 V) pin to set the VVREF at approximately 2.975 V. Select a value of 13 kΩ for R2 and 19.1 kΩ for R1 (the VREF resistor).
If current chopping is not required, the sense resistor can be removed and the source of the low side FET can be connected to ground.
SN and SP should be connected to the source of the low side FET and VREF should be connected to AVDD