Power Products FAQ QThe “Only GND pattern for primary side,” which is described in the RECOMMENDED FOOTPRINT of the data sheet for the MYBSP and MYBSS series isolated DC-DC converters for PoE, has the GND pattern only on the surface layer, so does that mean that other wiring is not allowed?

In consideration of the impact of noise, etc. from the DC-DC converter, a primary side GND with a stable electric potential should be used as the pattern.
If wiring is required, please check with your company's set before use.
Furthermore, the restrictions above do not apply to the inner layer or the rear.