36 Intel® 41110 Serial to Parallel PCI Bridge Design Guide
PCI-X Layout Guidelines
8.6.1 Embedded PCI-X 133 MHz
This section lists the routing recommendations for PCI-X 133 MHz without a slot. Figure 17 shows
the block diagram of this topology and Table 10 describes the routing recommendations.
Figure 17. Embedded PCI-X 133 MHz Topology
Table 10. Embedded PCI-X 133 MHz Routing Recommendations
Parameter Routing Guideline for Lower AD Bus
Reference Plane Route over an unbroken ground plane
Board Impedance 60 +/- 15%
Stripline Trace Spacing 12 mils from edge to edge
Microstrip Trace Spacing 18 mils, from edge to edge
Break Out 5 mils on 5 mils spacing. Maximum length of breakout region can be 500 mils
Group Spacing Spacing from other groups: 25 mils min, edge to edge
Trace Length 1 (TL1): From
41110 signal Ball to first
junction 1.75” min - 4.0” max
Trace Length 3 junction of
TL_EM1 and TL_EM2 to the
embedded device 1.25” min - 3.25” max
Length Matching
Requirements: Clocks coming form the clock driver must be on the same layer and length
matched to within 25 mils.
Number of vias 3 vias max per path
B2719 -01
EM1
EM2
TL1
TL_EM2 TL_EM1