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mouser.com/te 33 PSE and PD Circuitries Choosing a hybrid powering solution instead of PoDL also requires less PCB real estate. To get a better understanding of this, Figure 6 shows a typical coupling network for SPE. Both solutions have components for the data channel. This includes a PHY for data communication, a transformer for high voltage protection, a common-mode termination that can also include a common-mode choke (CMC) for higher frequencies, and an MDI connector that can handle SPE. However, with PoDL, we also require a coupling circuit at the PSE to feed the power to the data lines and a decoupling circuit at the PD to separate the power from the data lines. This is represented in Figure 6 as a low-pass filter. For currents up to 1A, the used PCB area of the coupled inductors can go up to 15 × 15mm with a height of 10mm. If going to higher currents of 1.5A, the coupled inductors must often be replaced by two separate inductors that require more volume to obtain a similar impedance. Here, the required PCB area can easily double. Hence, the hybrid powering solution that helps avoid these coupling and decoupling circuits becomes an excellent solution for higher current levels. Figure 6: Coupling network SPE and PoDL. (Source: TE Connectivity) Hybrid solutions require less PCB space than PoDL. They eliminate the need for coupling and decoupling circuits, which add 50 percent to PCB size and cause unwanted thermal losses. Hybrid solutions include different connector types for voltage levels and female connectors for safety, reducing the chance of contact with powered pins. Power Efficiency Ohmic losses in copper wires affect both PoDL and hybrid solutions. PoDL requires coupling circuits with Ohmic losses up to 1Ω, which causes heat. DC-DC converters have 80–95 percent efficiency— usually 90 percent. Hybrid solutions are more efficient, avoiding extra DC-DC converters needed for PoDL daisy-chaining. Conclusion PoDL and hybrid connectivity complement each other. PoDL offers thin, lightweight cables. Hybrid solutions support higher power levels, diverse topologies, and reduced PCB space. These benefits make hybrid connectivity ideal for industrial SPE applications.