General Description
The MAX5971A is a single-port, power-sourcing equipment (PSE) power controller designed for use in IEEE® 802.3af/at-compliant PSE. This device provides powered device (PD) discovery, classification, current limit, and DC and AC load-disconnect detections. The MAX5971A operates automatically without the need for any software programming and features an integrated power MOSFET and sense resistor. The device also supports new Class 5 and 2-event classification for detection and classification of high-power PDs. The MAX5971A provides up to 40W to a single port (Class 5 enabled) and still provides highcapacitance detection for legacy PDs.

FEATUREs
♦ IEEE 802.3af/at Compliant
♦ Up to 40W for Single-Port PSE Applications
♦ Integrated 0.5I Power MOSFET and Sense Resistor
♦ PD Detection and Classification
♦ Programmable Current Limit for Class 5 PDs
♦ High-Capacitance Detection for Legacy Devices
♦ Supports Both DC and AC Load Removal Detections
♦ Current Foldback and Duty Cycle-Controlled Current Limit
♦ LED Indicator for Port Status
♦ Direct Fast-Shutdown Control Capability
♦ Space-Saving, 28-Pin TQFN (5mm x 5mm) Package

APPLICATIONs
    Single-Port PSE End-Point Applications
    Single-Port PSE Power Injectors (Midspan Applications)
    Switches/Routers
    Industrial Automation Equipment
    Wireless LAN Access Point/WiMAX™ Base Station