IEI Integration ICE-DB-T6 - Manual (Page 79)

Type 6 Carrier Board Design Guide
Page 69
and 5 respectively. Inner Layer 3 and Layer 4 are asymmetric striplines that are
referenced to planes on Layers 2 and Layer 5.
Figure 4-2: Six-Layer Stack
NOTE:
ƒ All high-speed signals should reference solid ground planes through
the length of their routing and should not cross plane splits. To
guarantee this, both planes surrounding strip-lines should be GND.
ƒ IEI recommends that high-speed signal routing be done on internal,