This design showcases a low cost: Type-3: Class 6: 51W flyback converter for powered devices through Power over Ethernet. The TPS2373-3 PD controller provides detection and classification while also powering up the LM51551-Q1 PWM controller through its advanced startup feature. This design takes in a 42V-57V PoE input and outputs a 12V rail for applications such as IP network cameras and wireless access points.In need of an IEEE802.3bt-ready PSE controller? Check out the TPS23881.