The GND pad is used to dissipate
heat for the TPS25751D device. Connect the GND pins (pins 11, 12, 14 and 31)
to the Ground pad underneath the TPS25751D device. Connect the through hole
vias from the ground pad on the top layer to a copper pour on the bottom
layer to help dissipate heat. Additional vias can be added to improve
thermal dissipation.