SLVSE65C July 2018 – December 2023 DRV8847
PRODUCTION DATA
Refer to the PDF data sheet for device specific package drawings
Power dissipation in the DRV8847 device is dominated by the DC power dissipated in the output FET resistance (RDS(ON)_HS and RDS(ON)_LS). Additional power is dissipated because of PWM switching losses. These losses are dependent on the PWM frequency, rise and fall times, and VM supply voltages. These switching losses are typically on the order of 10% to 30% of the DC power dissipation.
Use Equation 33 to estimate the DC power dissipation of one H-bridge.
where
The value of RDS(ON)_HS and RDS(ON)_LS increases with temperature. Therefore, as the device heats, the power dissipation increases. This relationship must be considered when sizing the heat-sink.