Intel
ยฎ
EP80579 Integrated Processor Product Line May 2010
Order Number: 320068-005US 323
System Memory Interface (SODIMM)โIntel
ยฎ
EP80579 Integrated Processor Product Line
Board Routing Guidelines
Total Trace Length (TTL) = (L
PKG
+
L
BREAKOUT
+ L
ROUTE
+ L
BREAKIN
)
2.0 in - 5.0 in
โข Min TTL (DQS/DQS#)
= Min TTL (DQ/DM) -
200 mils
โข Max TTL (DQS/DQS#)
= Max TTL (DQ/DM) -
200 mils
Figure A-2
L
PKG
See the Intel
ยฎ
EP80579 Integrated Processor Product Line Datasheet for
package length information.
L
BREAKOUT
B = 0.8 in (max)
L
ROUTE
C = 1.0 in - 4.0 in
L
BREAKIN
D = 0.8 in (max)
Length/Skew Matching Rules
Length Tuning Requirements
โข Only length matching
is required within each
Byte lane. No signal
length matching is
required outside the
Byte lane. For
example, any signal
within Data Byte Lane
0 (DQ [0...7]) need not
be length matched to
DQS1
โขDQ/DM should match
each other to 20 mils
or less within the same
byte lane.
โข The trace length
difference between
DQS and DQS# should
not be more than 10
mils. - that is,
DQS[x] =
DQS[x]#ยฑ10 mils, x = 0..
7
โข Length match the data
strobes (DQS/DQS#)
to the associated data
mask and data (DQ/
DM) signals for each
Data Byte Lane:
โข Min TTL (DQS/DQS#)
= Min TTL (DQ/DM) -
200 mils
โข Max TTL (DQS/DQS#)
= Max TTL (DQ/DM) -
200 mils
Routing Rules
Layer Routing Requirements
Signals within a data byte lane must be routed on the
same layer.
DQS-to-Clock
Length match Strobe
(DQS/DQS#) to Clock
(CLK/CLK#) to within
500 mils:
โข DQS/DQS# = CLK/
CLK# ยฑ 500 mils
Table A-6. Data and Strobe Signal Group Routing Guidelines (Sheet 2 of 2)
Parameter
Routing Guidelines Figure
Data Byte Lane
Data & Data Mask Strobe