PCB Design Guidelines (HSSI, EMIF, MIPI, True Differential, PDN) User Guide: Agilex™ 5 FPGAs and SoCs
5.3. EMIF Breakout
For EMIF signal breakouts, use single-end traces. For more information on the DQS and CLK signals, routing requirements, impedance, and spacing guidelines, refer to EMIF PCB Routing Guidelines section.
The example in this section uses 3 mil minimum traces width and 3 mil spacing for microstrip and stripline routings. You can use wider traces for better impedance matching if routing can conform to the manufacturing requirements. The following figures show three layers of breakout examples which are the top layer, Layer 3, and Layer 5 to cover most of the breakout cases. Each image depicts one signal group breakout.
The figure shows the outer two rows that uses microstrip to adhere and meet the manufacturing rules. By using Layer 1 to Layer 3 and Layer 3 to Layer 5 micro vias, Layer 3 and Layer 5 can fan out signals. Keep at least one ground stitching via within 50 mil from the signal via. For other GPIO pins breakout, follow the similar ways as MBGA EMIF signals.