Intel CHIPSET 820E User Manual
Page 5
Intel
®
820E Chipset
R
Design Guide
5
ICH2 – LAN Interconnect Guidelines ........................................................ 103
Bus Topologies............................................................................. 104
Point-to-Point Interconnect ........................................................... 104
LOM/CNR Interconnect ................................................................ 104
Signal Routing and Layout............................................................ 105
Crosstalk Consideration ............................................................... 106
Impedances .................................................................................. 106
Line Termination........................................................................... 106
General LAN Routing Guidelines and Considerations .............................. 107
General Trace Routing Considerations ........................................ 107
Trace Geometry and Length....................................... 108
Signal Isolation ........................................................... 108
Power and Ground Connections .................................................. 108
General Power and Ground Plane Considerations .... 108
4-Layer Board Design................................................................... 110
82562EH Home/PNA* Guidelines ................................................... 112
Power and Ground Connections .................................................. 112
82562EH Component Placement ................ 112
Crystals and Oscillators ................................................................ 112
Phoneline HPNA Termination....................................................... 113
Critical Dimensions....................................................................... 114
Distance from Magnetics Module to Line RJ11.......... 114
2.22.3.5.2.
Distance from Intel
®
82562EH Component to
Magnetics Module ...................................................... 114
Distance from LPF to Phone RJ11............................. 115
82562EM Component Guidelines......................... 115
2.22.4.1.
Guidelines for Intel
82562ET / Intel
82562EM Component
Placement .................................................................................... 115
Crystals and Oscillators ................................................................ 116
2.22.4.3.
Intel
82562ET / Intel
82562EM Component Termination
Resistors .................................................................................... 116
Critical Dimensions....................................................................... 116
Distance from Magnetics Module to RJ45.................. 117
2.22.4.4.2.
Distance from the Intel
82562ET Component to the
Magnetics Module ...................................................... 118
Reducing Circuit Inductance......................................................... 118
Terminating Unused Connections ................................................ 118
Termination Plane Capacitance ................................. 118
82562ET/EM Disable Guidelines ....................................................... 119
2.22.6.
Intel
82562ET and Intel
82562EH Components’ Dual-Footprint
ICH2 Decoupling Recommendations ........................................................ 122
In-Circuit FWH Flash BIOS Programming ................................................ 124
FWH Flash BIOS VPP Design Guidelines ................................................ 124
Determine the Desired General Topology, Layout, and Routing............... 145