Intel EP80579 Manual page 343

Intel
Table B-29. Data and Strobe Signal Group Routing Guidelines (Sheet 2 of 2)
Trace-to-Trace spacing (e2e)
Clearance from other signals
Board Routing Guidelines
Total Trace Length (TTL) = (Lp +
L0 + L1 + L2 + L3)
Lp
L0
L1
L2
L3
Break-out/Break-in Trace Width
Break-out/Break-in Trace-to-Trace
Spacing
Series Termination
Series Resistor (Rsd)
Routing Length Matching Rules
DQS-to-DQS# Inter-pair Length
Matching
DQ/DM Data Byte Lane Length
Matching
DQS-to-DQ/DM Length Matching
DQS-to-Clock Length Matching
ODT Settings
Enable ODT
®
Intel EP80579 Integrated Processor Product Line
Platform Design Guide
343
®
EP80579 Integrated Processor Product Line—System Memory Interface (Memory Down)
Parameter
Data & Data Mask
15 mils (min)
20.0 mils (min)
Total Trace Length = 2.0 in - 6.0 in
Package Length:
• See the Intel
Microstrip Break-out:
• Trace Length = 0.5 in (max)
Board Route (Microstrip or Stripline)
• Trace Length = 1.5 in (min) - 4.0 in (max)
Microstrip Board Route:
• Trace Length = 0.3 in(max) if L1 is Stripline routed
Microstrip Break-in
• Trace Length = 0.5 in (max)
4.0 mils
4.0 mils
22Ω ±1%
Match total Length of data byte lane signals (DQ/DM) to
within 20 mils
• Max(DQ/DM) - Min(DQ/DM) </= 20 mils
Match total length of DQ/DM to DQS to within ±20 mils
• DQ/DM minimum Length = DQS - 20 mils
• DQ/DM maximum Length = DQS + 20 mils
Match total length of DQS to clocks to within ±500 mils
• DQS/DQS# minimum Length = Clock - 500 mils
• DQS/DQS# maximum Length = Clock + 500 mils
• Controller ODT = 120Ω
• SDRAM ODT = 150Ω
Routing Guidelines
Data Byte Lane
• Inter-pair Spacing:--
DQS/DQS# = 6 mils
(min)
• Pair-to-Pair Spacing:
15 mils (min)
®
EP80579 Integrated Processor Product Line
Datasheet for package length information.
on L3/L5/L6/L8
• Match total length of
DQS to DQS# to within
±10 mils
• DQS = DQS# ±10 mils
Figure
Strobe
May 2010
Order Number: 320068-005US