Continue with the previous article:
When a signal transitions to a different layer with a different reference plane, stitching capacitors should be implemented. This allows the return current to flow from the ground to the power layer through the stitching capacitors, as shown in the cover figure. Additionally, when considering differential pairs, the placement and routing of stitching capacitors should be symmetrical to maintain the balance and integrity of the differential signal.
In design, high-speed signals should not be routed at the edges of the reference plane or near the PCB boundaries, as this can adversely affect the trace impedance, leading to signal integrity issues such as reflections and impedance mismatches.
In the next article, we will introduce the analog ground and digital ground in PCB routing.
