,p> To this day, Power over Ethernet (PoE) continues to gain popularity in today’s networking world. The 12.95 W delivered to the powered device (PD) input supplied by the Power Sourcing Equipment (PSE) is a universal supply. Each PD provides its own dc-dc conversion from a nominal 48-V supply, thus eliminating the need for a correct-voltage wall adapter. However, higher power devices cannot take advantage of standard PoE because of its power limitations, and must rely on a large wall adapter as their primary supply. The new LTC4268-1 breaks this power barrier by allowing for power of up to 35 W for such power-hungry two-pair PoE applications. The LTC4268-1 provides a complete solution by integrating a high power PD interface control with an isolated fly back controller.