TPS68470: Layer needed to route TPS68470

Anthony,
It is possible to route the TPS68470 on 4 layers. The theory is that you take the max row or column count divided by 2. This will give you a good idea as to how many layers you need. in this case the ball grid array is 8x7. (8/2 = 4) You will need to use some high density techniques to make this work, such as using blind vias. Blind vias can add cost to your board so check with your board manufacture determine the impact. In many cases the cost is trivial. Let me know if you need more information.