Table of Contents
Advertisement
®
®
Intel
Pentium
M Processor and Intel
Memory Interface Routing Guidelines
Table 33.
Dual Channel Source Synchronous Signal Group Routing Guidelines
Parameter
3
Signal Group
Topology
Reference Plane
MCH to Rs Trace
Impedance (Z
)
0
Rs to Rtt Trace Impedance
(Z
)
0
MCH to Rs Trace Width
Rs to Rtt Trace Width
Nominal Trace Spacing
MCH to DIMM1 Trace
4
Length
Rs to DIMM1 Trace Length
DIMM to DIMM Trace Length Not Supported
DIMM to Rtt Trace Length
Series Resistor (Rs)
Termination Resistor (Rtt)
8
MCH Breakout Guidelines
Length Tuning
Requirements
NOTES:
1. No Rs is required. Instead, change the impedance at the first DIMM pin.
2. The DQS pair in the group must also be tuned to each other with this parameter. The DQ and DQS lines in the same group
must be length tuned to all DIMMs. Tune all lengths to the Intel
3. Route all data signals and their associated strobes on the same layer from MCH to Rtt.
4. The MCH to DIMM1 trace length is defined as Intel E7501 MCH die pad (PCB trace velocity equivalent, see
"Length
Tuning") to DIMM1 pin.
5. Within the same group, this length range should not vary by more than 50 mils. However, the length may be anywhere from
1.0" to 1.2".
6. Ensure angled DIMM connector pin length differences are accounted for when tuning lengths.
7. Within the same group, this length range should not vary by more than 50 mils. However, the length may be anywhere from
1.8" to 2.2".
8. Breakout distance is measured from outer ball array.
80
®
E7501 Chipset Platform
1-DIMM
2-DIMM
Solution
Solution
6
6
6
0°
, 25°
, 90°
25°
DQ[63:0], CB[7:0], DQS[17:0]
50 Ω ± 10%
50 Ω ± 10%
50 Ω ± 10%
50 Ω ± 10%
5 mils
5 mils
5 mils
5 mils
15 mils ± 1 mil
15 mils ± 1 mil
1.8" to 5.5"
1.8" to 4.5"
0.1" to 0.8"
0.1" to 0.8"
1.8" to 2.2"
7
± 50 mil
< 0.8"
< 0.8"
10 Ω ± 2%
10 Ω ± 2%
39.2 Ω ± 1%
39.2 Ω ± 1%
5/5 (1:1),
5/5 (1:1),
< 500 mils
< 500 mils
DQ to DQS:
DQ to DQS: ±
2
2
25 mil
± 25 mil
2-DIMM
3-DIMM
Solution
Solution
90°
90°
Daisy Chain
Ground
50 Ω ± 10%
50 Ω ± 10%
50 Ω ± 10%
50 Ω ± 10%
5 mils
5 mils
5 mils
5 mils
15 mils ± 1 mil 15 mils ± 1 mil
1.8" to 6.0"
3.5" to 6.3"
0.1" to 0.8"
0.1" to 0.8"
1.0" to 1.2"
1.0" to 1.2"
5
5
± 50 mil
± 50 mil
< 0.8"
< 0.8"
10 Ω ± 2%
10 Ω ± 2%
39.2 Ω ± 1%
39.2 Ω ± 1%
5/5 (1:1),
5/5 (1:1),
< 500 mils
< 500 mils
DQ to DQS: ±
DQ to DQS: ±
2
2
25 mil
25 mil
®
E7501 MCH package trace lengths.
4-DIMM
Solution
Reference
90°
Figure 40
Figure 34
45 Ω ± 10%
Table 31
55 Ω ± 10%
Table 31
6 mils
Figure 34
4 mils
Figure 34
15 mils ± 1 mil
Figure 34
6.1" to 6.3"
Figure 40
0.1" to 0.8"
Figure 40
1.0" to 1.12"
Figure 40
5
± 50 mil
0.3" to 1.3"
Figure 40
Not
Figure 40
1
Applicable
34.8 Ω ± 1%
Figure 40
5/5 (1:1),
< 500 mils
DQ to DQS: ±
Figure
41,
2
25 mil
Section 12.6
Section 12.6,
Design Guide
Advertisement
Table of Contents
