SNLS614A September 2018 – December 2018 DP83869HM
To meet signal integrity and performance requirements, at minimum a 4-layer PCB should be used. However a 6-layer board is recommended. See Figure 120 for the recommended layer stack ups for 4, 6, and 8-layer boards. These are recommendations not requirements, other configurations can be used as per system requirements.
Within a PCB, it may be desirable to run traces using different methods, microstrip vs. stripline, depending on the location of the signal on the PCB. For example, it may be desirable to change layer stacking where an isolated chassis ground plane is used. Figure 121 shows alternative PCB stacking options.