LTC4278CDKD#PBF

Overview

The LTC4278CDKD#PBF is a Powered Device (PD) controller compliant with IEEE 802.3at and 802.3af standards, designed for Power over Ethernet applications. It integrates a power switch and supports up to 25.5 W of output power. The device operates within a source voltage range of 37.2 V to 60 V and features a maximum supply current of 1.35 mA. It utilizes a 32-lead DFN package measuring 7x4 mm with an exposed pad, suitable for surface-mount installation. The operational temperature range extends from 0°C to 70°C.

Feature Summary

• Supports synchronous no-optocoupler flyback control for efficient isolated power conversion
• Integrates a high-voltage power switch for direct PoE line connection
• Includes auxiliary detection capability for enhanced port classification
• Complies with IEEE 802.3at and 802.3af Powered Device standards

Applications

• IEEE 802.3at (PoE+) Powered Devices
• IEEE 802.3af (PoE) Powered Devices
• Isolated power supplies for network equipment
• Synchronous flyback converters in LAN applications

Procurement Notes

Verify the specific suffix #PBF indicates tube packaging rather than reel packaging when reviewing distributor listings. Confirm the manufacturer part number matches exactly to avoid confusion with tape-and-reel variants like #TRPBF. Ensure the component meets RoHS compliance requirements for your region. Cross-reference the 32-DFN package dimensions against your PCB footprint library. Validate that the supplier provides official Analog Devices documentation for the specific lot code.

Selection Notes

Choose this component when designing IEEE 802.3at or 802.3af powered devices requiring integrated power switching and flyback control. It is suitable for applications needing auxiliary detection and synchronous rectification without optocouplers. Consider the 32-DFN package size for space-constrained designs. Verify that the input voltage range of 37.2 V to 60 V aligns with your PoE port specifications. Ensure thermal management strategies account for the exposed pad design.

Part Context

This part belongs to the LTC4278 series of PoE controllers from Analog Devices. It is functionally related to other PD controllers like the LTC4268 but offers specific integration for synchronous flyback architectures. The device simplifies design by combining classification, detection, and power delivery functions into a single IC. It serves as a key component in modern network infrastructure powering solutions.

Replacement Considerations

Public confirmed substitute part numbers are not available in the provided documentation. Check for pin-compatible alternatives within the Analog Devices portfolio if availability is an issue.