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