This Figure shows the RLDRAM 3 memory data signals point-to-point routing.
Table: RLDRAM 3 Memory Impedance, Length, and Spacing Guidelines for Data Signals shows the RLDRAM 3 memory impedance, length, and spacing guidelines for data signals.
|
Parameter |
L0 (Device Breakout) |
L1 (Main PCB) |
L2 (DRAM Breakout) |
Units |
|---|---|---|---|---|
|
Trace type |
Stripline |
Stripline |
Stripline |
– |
|
dq impedance Z0 |
50±10% |
39±10% |
50±10% |
W |
|
Trace width (nominal) |
4.0 |
6.0 |
4.0 |
mil |
|
Trace length (nominal) |
0.0~0.8/1.2(1) |
0.0~4.0 |
0.0~0.25 |
inches |
|
Spacing in byte (minimum) |
4.0 |
8.0 |
4.0 |
mil |
|
Spacing byte to byte (minimum) |
4.0 |
20 |
4.0 |
mil |
|
dq to dk/qk spacing (minimum) |
4.0 |
20 |
8.0 |
mil |
|
Spacing to other group signals (minimum) |
8.0 |
30 |
30 |
mil |
|
Maximum PCB via count |
2 |
– |
||
|
Notes: 1.See item 2 in General Memory Routing Guidelines. |
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