PCI-X Layout Guidelines

8.6.4PCI 66 MHz Embedded Topology

Figure 20 and Table 13 provide routing details for a topology with an embedded PCI 66 MHz design.

Figure 20. PCI 66 MHz Embedded Topology

EM1

EM3

TL EM1

TL EM3

TL1

TL2

TL EM2

TL EM4

EM2

EM4

B2722 -01

Table 13.

PCI 66 MHz Embedded Table

 

 

 

 

 

Parameter

Routing Guideline for Lower AD Bus

 

 

 

 

Reference Plane

Route over an unbroken ground plane

 

 

 

 

Board Impedance

60 +/- 15%

 

 

 

 

Microstrip Trace Spacing

18 mils center to center

 

 

 

 

Stripline Trace Spacing

12 mils center to center

 

 

 

 

Group Spacing

Spacing from other groups: 25 mils min, edge to edge

 

 

 

 

Breakout

5 mils on 5 mils spacing. Maximum length of breakout

 

region can be 500 mils.

 

 

 

 

 

 

Trace Length 1 TL1: From 41110 signal Ball to first

5.0” max

 

junction

 

 

Trace Length TL2 between junctions

0.5” min - 3.5” max

 

 

 

 

Trace Length TL_EM1 to TL_EM4 from junction to

2.0” min - 3.0” max

 

embedded devices

 

 

Length Matching Requirements

Clocks coming from the clock driver must be length

 

matched to within 25 mils.

 

 

 

 

 

 

Number of vias

4 vias max.

 

 

 

P

Intel® 41110 Serial to Parallel PCI Bridge Design Guide

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Intel 41110 manual PCI 66 MHz Embedded Topology, PCI 66 MHz Embedded Table