SLVSCC0D November 2013 – October 2019 DRV8850
Power dissipation in the DRV8850 device is the sum of the motor driver power dissipation and the LDO voltage regulator dissipation.
The LDO dissipation is calculated simply by (VIN – VOUT) × IOUT.
The power dissipation in the motor driver is dominated by the power dissipated in the output FET resistance, or RDS(ON). Power dissipation can be estimated by:
The maximum amount of power that can be dissipated in the device is dependent on ambient temperature and heat sinking.
Note that RDS(ON) increases with temperature, so as the device heats, the power dissipation increases.