Integrated Power-Over-LAN Controller Meets IEEE Standard

The MAX5922 is a fully integrated single-port 48-V power switch that fully complies with the IEEE 802.3af standard for Power-over-Ethernet (PoE, also known as Power over Local-Area Network, or LAN) systems. Designed specifically for use in power-sourcing equipment (PSE), the MAX5922 performs power device discovery, classification, current limiting, and other PSE functions. The chip suits powered switch/router systems and midspan systems.

The chip operates from 32- to 60-V rails and features an integrated 0.45-Ω power MOSFET. During startup, the MAX5922 limits output voltage and current slew rate to minimize electromagnetic interference. The IC also provides programmable current limiting to protect the load. Pricing for the MAX5922, housed in a 20-pin TSSOP, starts at $3 in lots of 1000.