Texas Instruments LM5072MH-50

Description
The LM5072 is a Powered Device (PD) interface and Pulse-Width-Modulation (PWM) controller that provides a complete power solution for IEEE 802.3af compliant PDs in Power over Ethernet (PoE) networks. It integrates functions for both a PD powered interface and a DC-DC converter, minimizing external components. The LM5072 supports auxiliary power sources such as AC adapters in various configurations. Its low RDS(ON) PD interface hot swap MOSFET and programmable DC current limit extend its applications to higher power levels than 802.3af compliant PD devices. The 100V maximum voltage rating simplifies transient voltage suppressor selection. The LM5072 includes an easy-to-use PWM controller for single-ended power supply topologies (flyback, forward, buck). Its peak current mode control scheme provides line feed-forward, cycle-by-cycle current limit, and simplified feedback loop compensation. Two versions are available: -80 suffix (80% maximum duty cycle with built-in slope compensation) and -50 suffix (50% maximum duty cycle, no slope compensation).

Features

PD Interface
Fully IEEE 802.3af compliant PD interface
Versatile auxiliary power options
9V minimum auxiliary power operating range
100V maximum input voltage rating
Simplified application diagram
Programmable DC current limit up to 800mA
100V, 0.72Ω hot swap MOSFET
Integrated PD signature resistor
Integrated PoE input UVLO
Programmable inrush current limit
PD classification capability
Power good indicator
Thermal shutdown protection

PWM Controller
Current mode PWM controller
100V start-up regulator
Error amplifier with 2% voltage reference
Supports isolated and non-isolated applications
Programmable oscillator frequency
Programmable soft-start
800mA peak gate driver
80% maximum duty cycle with built-in slope compensation (-80 device)
50% maximum duty cycle, no slope compensation (-50 device)

Applications
IEEE 802.3af compliant PoE powered devices
Non-compliant, application-specific devices
Higher power Ethernet powered devices