1 four-layer stack-up, 2 six-layer stack-up, Figure 5-1: four layers stack – IEI Integration ICE-DB-9S User Manual
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ICE Module
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5.3.1 Four-Layer Stack-up
Figure 5-1 below is an example of a four layer stack-up. Layers L1 and L4 are used for
signal routing. Layers L2 and L3 are used for solid ground and power planes
respectively. Microstrips on Layers 1 and 4 reference ground and power planes on
Layers 2 and 3 respectively. In some cases, it may be advantageous to swap the GND
and PWR planes. This allows Layer 4 to be GND referenced. Layer 4 is clear of parts
and may be the preferred primary routing layer.
Figure 5-1: Four Layers Stack
5.3.2 Six-Layer Stack-up
Figure 5-2 below is an example of a six layer stack-up. Layers L1, L3, L4 and L6 are
used for signal-routing. Layers L2 and L5 are power and ground planes respectively.
Microstrips on Layers 1 and 6 reference solid ground and power planes on Layers 2
and 5 respectively. Inner Layers 3 and 4 are asymmetric striplines that are referenced
to planes on Layers 2 and 5.