LT4276CIUFD#TRPBF

Overview

The LT4276CIUFD#TRPBF is a Powered Device (PD) controller supporting IEEE 802.3at (PoE+) and LTPoE++ standards. It integrates an isolated switching regulator controller for forward and flyback topologies with auxiliary power support. Input voltage ranges from 37V to 57V. The device supports output configurations such as 12V at 7A (90W) in forward mode, or 5V at 7A (38.7W) and 5V at 4.7A (25.5W) in flyback mode. It operates within a temperature range of -40°C to +125°C and utilizes a 28-WFQFN package.

Feature Summary

• Supports IEEE 802.3at PoE+ and LTPoE++ Powered Device classifications
• Integrates isolated switching regulator controller for synchronous forward and flyback topologies
• Includes auxiliary power input capability for enhanced operational flexibility
• Pin-for-pin compatible across the LT4276 family for design scalability

Applications

• 90W LTPoE++ power supplies operating in forward topology
• 38.7W LTPoE++ power supplies operating in flyback topology
• 25.5W Type 2 PoE+ power supplies operating in flyback topology

Procurement Notes

Verify the specific suffix TRPBF indicates tape and reel packaging when ordering. Confirm that the CIUFD designation corresponds to the required thermal and electrical specifications for your application. Ensure compatibility with existing PCB footprints designed for the 28-WFQFN package. Cross-reference the latest datasheet revision to confirm pinout integrity against previous LT4276 variants.

Selection Notes

Select this component when designing systems requiring high-power density via Ethernet cabling. Choose the LT4276CIUFD#TRPBF specifically for applications needing LTPoE++ support alongside standard PoE+. Consider the integrated controller features to reduce external component count in isolated DC-DC converter designs. Evaluate the auxiliary power support if system uptime during cable removal is critical.

Part Context

This part belongs to the LT4276 family of PD controllers from Analog Devices. The family provides pin-for-pin compatibility between different power class variants, allowing designers to scale power output without changing the footprint. The LT4276 series bridges legacy PoE standards with newer LTPoE++ capabilities, serving as a central control element for powered devices in network infrastructure.

Replacement Considerations

LT4276AHUFD#TRPBF, LT4276BIUFD#TRPBF, LT4276CHUFD#TRPBF, LT4276BHUFD#PBF.