Analog Devices Inc.

LTC4278CDKD

LTC4278CDKD Description

The LTC4278CDKD from Analog Devices Inc. is a highly integrated Power over Ethernet (PoE) controller designed for Powered Device (PD) applications. This 1-channel controller complies with IEEE 802.3af (PoE) and 802.3at (PoE+) standards, supporting a wide input voltage range of 37.2V to 60V and delivering up to 25.5W of power. Housed in a 32-DFN package, it features surface-mount technology for compact PCB designs. Although marked as obsolete, its robust design and auxiliary sense capability make it a reliable choice for legacy systems requiring PoE power management.

LTC4278CDKD Features

• Single-Channel PD Controller: Integrates DC/DC conversion and PoE negotiation in one IC.
• Wide Voltage Range: Operates from 37.2V to 60V, suitable for high-power PoE+ applications.
• Low Supply Current: 1.35mA (max) ensures efficient power management.
• Auxiliary Sense: Enables detection of non-PoE power sources for flexible system design.
• Internal Switches: Reduces external component count, simplifying board layout.
• Industrial-Grade Reliability: MSL 1 (Unlimited) moisture sensitivity ensures durability in storage.

LTC4278CDKD Applications

• IP Cameras & Surveillance Systems: Provides stable power for PoE-enabled security devices.
• Wireless Access Points: Simplifies power delivery in network infrastructure.
• VoIP Phones: Ensures reliable power and data over a single Ethernet cable.
• Industrial IoT Devices: Ideal for rugged environments requiring PoE compliance.
• Legacy PoE Upgrades: Suitable for retrofitting older systems with modern PoE+ capabilities.

Conclusion of LTC4278CDKD

The LTC4278CDKD stands out for its high integration, compliance with PoE/PoE+ standards, and robust auxiliary power sensing. While obsolete, its low power consumption, internal switching, and wide voltage range make it a viable solution for legacy or cost-sensitive PoE applications. Engineers designing networked devices, industrial systems, or surveillance equipment may find this IC particularly useful for its balance of performance and simplicity. For new designs, consider Analog Devices' active PoE controllers with updated features.