Specific Routing Configurations; Offset Routing; Zig-Zag Or Slanted Routing; An Example Of Offset Routing - Intel Quark SoC X1000 Design Manual

edge of the board. Those lengths should not be considered in this analysis.
The total length is the Root Square Sum of total vertical and horizontal lengths that run parallel to the
weave:
2. The table represents an approximation only, based on simulations of "representative" topology. The
exact fiber weave may vary, depending on the exact topology.
2.6.3

Specific Routing Configurations

Some platforms might have their components laid out in a manner that requires non-
orthogonal (to the PCB board edge) routing for their high-speed busses. Orthogonal
routing up to a maximum length of 2" does not result in a noticeable impact on the
differential signals. However, there could be a significant amount of AC Common-Mode
voltage introduced between the differential pair that the platform designer will need to
consider.
2.6.4

Offset Routing

This involves routing the trace in a straight line with offset in the middle equal to a
glass bundle pitch. The glass bundle pitch differs by materials and direction and is
dependent on the particular manufacturing process. An example is shown in
For this technique to be applied, a PCB layout tool with this capability would be
required.
Figure 12.

An Example of Offset Routing

2.6.5

Zig-Zag or Slanted Routing

If the weave is aligned to the PCB edges, follow a zig-zag or slanted routing of
differential traces. Maintain a minimum angle of 10 degrees between the trace and
fiber weave. This will lead to traces that are angled relative to the PCB edge.
is an example of zig-zag routing.
be applied, a PCB layout tool with this capability would be required.
®
Intel Quark™ SoC X1000
PDG
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Intel Quark™ SoC X1000—Stack-Up and PCB Considerations
2 2
   
Length = H + H +
1 2
where: H = length of each segment routed horizontally, and
x
V =length of each segment routed vertically
x
Figure 14
2 2 2
      
H + V + V + V
3 1 2 3
shows slanted routing. For this technique to
Order Number: 330258-002US
2
 
+
Figure 12.
Figure 13
June 2014