LT4275AHDD#PBF

Overview

The LT4275AHDD#PBF is a Powered Device (PD) controller from the LT4275 family, designed for IEEE 802.3 and LTPoE++ applications. It supports power levels up to 90W using a proprietary classification scheme. The device operates with an input voltage range of 9V to 60V and delivers 25W output power in typical configurations. It features a 10-lead DFN package (3mm x 3mm) with exposed pad, suitable for surface mount installation. The controller includes an internal charge pump for N-channel MOSFET drive, integrated signature resistance, and auxiliary power support.

Feature Summary

• Supports LTPoE++ classification for high-power delivery up to 90W alongside standard IEEE 802.3af/at compliance
• Utilizes an internal charge pump to drive external N-channel MOSFETs, minimizing conduction losses and thermal dissipation
• Includes integrated signature resistor and programmable auxiliary power input for flexible system design
• Provides thermal protection and undervoltage lockout for robust operation in demanding environments

Applications

• High-power wireless data systems
• Outdoor security camera equipment
• Commercial and public information displays
• High-temperature industrial applications

Procurement Notes

Verify the specific suffix DD indicates the DFN-10 package configuration when sourcing. Confirm that the AH variant aligns with required LTPoE++ power levels. Check current availability status as supply may be restricted. Ensure compatibility with external N-channel MOSFET selection for optimal efficiency. Validate auxiliary input requirements against system design specifications.

Selection Notes

Select this component for designs requiring high-power PoE delivery beyond standard Type 4 limits. The LT4275A variant specifically enables proprietary LTPoE++ classification schemes. Consider the 3mm x 3mm DFN footprint for space-constrained layouts. Evaluate the need for auxiliary power inputs if operating near voltage thresholds. Compare against LT4275B or C variants if lower power standards suffice.

Part Context

The LT4275 series comprises pin-compatible PD controllers supporting various PoE standards. The LT4275A model distinguishes itself by enabling LTPoE++ power levels up to 90W. Other variants like LT4275B and LT4275C target standard IEEE 802.3at and af applications respectively. This family simplifies design through integrated features and external MOSFET control.

Replacement Considerations

Direct substitute part numbers are not explicitly confirmed in the provided documentation for this specific suffix. Review LT4275AIDD#PBF for equivalent functionality in alternative packaging. Verify pin compatibility before substituting with other LT4275 family members.