Linear Technology LTC4268CDKD-1#TRPBF

Description
The LTC4268-1 is an integrated Powered Device (PD) controller and switching regulator designed for IEEE 802.3af and high power PoE applications up to 35W. It features a precision dual current limit to ensure interoperability success while enabling high power applications with a 750mA operational current limit.
The LTC4268-1 synchronous, current-mode, flyback controller generates multiple supply rails in a single conversion, providing high system efficiency and tight regulation across all outputs. It utilizes Linear Technology's patented No-Opto feedback topology to provide full IEEE 802.3af isolation without the need for opto-isolator circuitry.

Features
Robust 35W PD Front End
IEEE 802.3af Compliant
Rugged 750mA Power MOSFET with Precision Dual Level Current Limit
High Performance Synchronous Flyback Controller
IEEE Isolation Obtained Without an Opto-Isolator
Adjustable Frequency from 50kHz to 250kHz
Tight Multi-Output Regulation with Load Compensation
Onboard 25k Signature Resistor
Programmable Classification Current to 75mA
Complete Thermal and Over-Current Protection
Available in Compact 32-Pin 7mm x 4mm DFN Package

Applications
VoIP Phones with Advanced Display Options
Dual-Radio Wireless Access Points
PTZ Security Cameras
RFID Readers
Industrial Controls
Magnetic Card Readers
High Power PoE Systems