I have a dual analog output PCBA that I am routing. The analog output component selected is two TI DAC7750IRHAR DACs.
These DACs are controlled via SPI lines. I had originally intended to place both of those on the same layer and route the control signals between them and the controller, but due to space constraints, nearby connectors, etc., I found it quite advantageous from a routing standpoint if I had these two components on opposite sides of the board and placed directly on top of each other.
However, the recommended footprint shown at the end of the datasheet includes thru-vias in the thermal ground pad that are intended to help with heat dissipation.
I haven't yet determined if my circuit will require the extra heat sinking (TI's documentation suggests that it's optional), but this does bring up the question about the feasibility of placing the components like this. Will the thru-vias in the thermal pad cause assembly problems? I'd prefer to avoid having to tent or plug them.
I'm not concerned about the vias from each footprint "interfering" with each other. I have placed them directly on top of each other, so they all line up perfectly. I could also change the footprints so that only one of them has the vias, or so that each only defines half the vias and they don't interfere. I'm only concerned with how the vias showing up in the ground pads will affect assembly.