SLIS175 November 2016 DRV8872-Q1
The PowerPAD package uses an exposed pad to remove heat from the device. For proper operation, this pad must be thermally connected to copper on the PCB to dissipate heat. On a multi-layer PCB with a ground plane, this connection can be accomplished by adding a number of vias to connect the thermal pad to the ground plane.
On PCBs without internal planes, a copper area can be added on either side of the PCB to dissipate heat. If the copper area is on the opposite side of the PCB from the device, thermal vias are used to transfer the heat between top and bottom layers.
For details about how to design the PCB, refer to the TI application report, PowerPAD™ Thermally Enhanced Package (SLMA002), and the TI application brief, PowerPAD Made Easy™ (SLMA004), available at www.ti.com. In general, the more copper area that can be provided, the more power can be dissipated.