MAX5992AETG+

MAX5992AETG+ Features

● IEEE 802.3af/at Compliant● UPoE Compatible● High-Power 2x2P/Multi-PD Synchronization /Multi-PD Redundancy● Integrated Active FET Bridge Control andBack-Powering Protection● Selectable UVLO for Medical/Industrial Applications● 2-Level Inrush-Current Control● Intelligent MPS● Simplified Wall Adapter Interface for Seamless PowerTransition● Ultra-Low-Power/Sleep Mode● 2-Event Classification or an External Wall AdapterIndicator Output● PoE Classification 0 to 5● Gate Driver for External Isolation MOSFET● Selectable Current Limit and Foldback● RJ45 12V Supply Input● 6.5s Sleep Mode Delay

MAX5992AETG+ General Description

The MAX5992A/MAX5992B multisource, high-power,high-performance powered device (PD) controllersprovide a complete interface control for PDs to complywith the IEEE® 802.3af/at standard in a Power-over-Ethernet (PoE) system. The devices provide the PDwith a detection signature, classification signature, andan isolation MOSFET driver with current-limit control. Inaddition, the intelligent maintain power signature (MPS)and active FET bridge control make the PD more powerefficient. The devices feature a SIG_OK output signalfor high-power Multi-2P PD applications. The selectableinrush-current modes allow Multi-PD, fiber-to-the-home/fiber-to-the-building (FTTH /FTTB) operation in redundancyapplications. The devices feature an input UVLO, widehysteresis, and long deglitch time to compensate for twisted-pair cable resistive drop to assure glitch-free transitionduring power-on /power-off conditions. The devices canoperate from a 20.8V low-voltage supply by a selectableUVLO. The devices can withstand up to 100V at the input.The devices support a 2-Event classification method asspecified in the IEEE 802.3at standard and provide asignal to indicate when probed by Type 2 power-sourcingequipment (PSE). The devices detect the presence ofa wall adapter power-source connection and allow asmooth switchover from the PoE power source to the wallpower adapter. Moreover, the selectable WAD_SELsupports seamless power transition from a wall adapter toPoE if PoE is already enabled.The devices also provide a power-good (PG) signal,2-level current limit, foldback, and overtemperatureprotection. A sleep mode feature provides low-powerconsumption while supporting MPS. An ultra-low powersleep mode feature further reduces power consumptionto comply with ultra-low power requirements while stillsupporting MPS. The devices also feature an LED driverthat is automatically activated during sleep/ultra-lowpower sleep/MPS mode. The MAX5992A has 38.6V PoEUVLO and the MAX5992B has 35.4V PoE UVLO andfeature a 6.5s sleep mode delay.The MAX5992A/MAX5992B are available in a 24-pin,4mm x 4mm, TQFN power package and are rated over the-40°C to +85°C extended temperature range.

MAX5992AETG+ Applications

● IEEE 802.3af/at-Powered Devices (PD)● Universal Power-over-Ethernet (UPoE)● Femtocell, Picocell, Microcell● High-Power 2x2P PD● Multi-PD Redundancy● Fiber-to-the-Home/Building (FTTH/FTTB)● IP Phones● Wireless Access Nodes● IP Security Cameras (IPC)● WiMAX® Base Stations