On the lay out guide lines for DRV8312 in Data Sheet, on Page 23 - Figure 16 - titled "opposite side", are shown 6 holes on top and bottom. These are spaced 2 mm apart. The questions are:
(1) What these holes are for? What is the purpose they serve?
(2) Do they need to be plated thru?
(3) Do they need to be connected to the ground?
Newton,
1) Please see figure 16. These are part of the thermal via pattern. They provide a thermal path for heat to flow from the top side to the bottom side for thermal relief. They are not absolutely necessary and can be omitted. The important vias are the ones right under the device.
2) Yes, they should be.
3) Yes, the exposed PowerPad on the bottom of the device needs to be connected to GND and these vias connect the top side GND plane to the bottom side.
Ryan Kehr
Motor Drive Application Manager