Power over Ethernet (PoE) is a widely adopted technology used to transfer both data and electrical power over an RJ-45 cable. ST offers solutions for PoE applications, on the powered devices (PD) side, compliant with both the more recent IEEE 802.3at specification, commonly known as PoE+, and the former IEEE 802.3af (PoE).
The design of power supply sections for all powered devices can be greatly simplified with the PM880x family, integrating a PoE interface and a current-mode PWM controller. The PoE interface incorporates all the functions required by the communication standard, including detection, classification, undervoltage lockout (UVLO) and in-rush current limitation.
