Ground Connections; Power Connections; Dogbone Via Pattern - Intel 740 Design Manual

2.2.3.2

Ground Connections

All lands in the four corners and center are V
connect to an adjacent via which passes through to the solder side of the board, one via per ball,
with a trace as wide as the via. Heat will dissipate through these vias to the GND plane as well as to
the air on the solder side.
Figure 2-8. Dogbone Via Pattern
2.2.3.3

Power Connections

The VCC2 plane should be as wide as practical for high current-carrying capacity. Because of the
interspersing of VCC2 and VCC3 pins on the Intel740™ graphics accelerator, a polygon will be
needed on one of the signal layers to extend the VCC3 plane to the isolated VCC3 pins
(Figure 2-9). The VCC2 polygon is a separate plane on the VCC Layer; the darker VCC3 polygon
is a power flood on the solder side and connects to the VCC3 plane on the VCC Layer through vias.
Intel740™ Graphics Accelerator Design Guide
(GND). Thermal analysis requires that each V
ss
Addin Card Design
ball
ss
2-9