In the FG484 / FGG484 Package Drawing, PK081 (v1.0), both a 2-Layer dimension and a 4-Layer dimension are listed. Which one should I use?
The only Xilinx devices which use the FG484 and the FGG484 packages are the Spartan-3A and the Spartan-3AN devices. Both of these devices use the 4-Layer package.
None of the Xilinx devices use the 2-Layer FG484 or FGG484, so the note referencing the 2-Layer dimensions will be removed in the next revision.
To see the Fine-Pitch (FG484/FGG484) BGA Package drawing, please go to: