Features and Benefits
- Four PSE Ports
- Two Power Channels per Port
- Fully Compliant IEEE 802.3bt Type 3 and 4 PSE
- Compliant Support for Type 1, 2, 3, and 4 PDs
- Low Power Path Dissipation per Channel
- 150mΩ Sense Resistance
- 30mΩ or Lower MOSFET RDS(ON)
- Chipset Provides Electrical Isolation
- Eliminates Optos and Isolated 3.3V Supply
- Very High Reliability Multipoint PD Detection
- Connection Check Distinguishes Single-Signature and Dual-Signature PDs
- Continuous, Dedicated Per-Port Power and Current Monitoring
- Per-Port Power Policing
- 1MHz I2C Compatible Serial Control Interface
- Pin or I2C Programmable PD Power Up to 71.3W
- Available in a 40-Lead 6mm × 6mm (LTC4292) and 24-Lead 4mm × 4mm (LTC4291-1) QFN Packages
The LTC4291-1/LTC4292 chipset is a 4-port power sourcing equipment (PSE) controller designed for use in IEEE 802.3bt Type 3 and 4 compliant Power over Ethernet (PoE) systems. The LTC4291-1/LTC4292 is designed to power compliant 802.3af, 802.3at, and 802.3bt PDs. The LTC4291-1/LTC4292 chipset delivers lowest-in-industry heat dissipation by utilizing low RDS(ON) external MOSFETs and 0.15Ω sense resistance per power channel. A transformer-isolated communication protocol replaces expensive opto-couplers and complex isolated 3.3V supply, resulting in significant BOM cost savings.
Advanced power management features include per-port 14-bit current monitoring, programmable current limit, and versatile fast shutdown of preselected ports. Advanced power management host software is available under a no-cost license. PD detection uses a proprietary multipoint detection mechanism ensuring excellent immunity from false PD identification. Autoclass and 5-event physical classification are supported. The LTC4291-1/LTC4292 includes an I2C serial interface operable up to 1MHz. The LTC4291-1/LTC4292 is pin or I2C programmable to negotiate PD delivered power up to 71.3W.
Product Lifecycle Production
At least one model within this product family is in production and available for purchase. The product is appropriate for new designs but newer alternatives may exist.
Evaluation Kits (1)
Demonstration circuit 2685B is a 4-port IEEE 802.3bt power sourcing equipment (PSE) composed of a DC2684A-B (daughter card) and DC2683A (motherboard). The DC2685B (kit) is used for evaluation of the LTC4291-1/LTC4292 PSE chipset. Up to four IEEE 802.3af, IEEE 802.3at, or IEEE 802.3bt powered devices (PDs) can be connected and powered from this system using a single power supply. A DC590 is connected to the DC2685B for I2C interfacing with QuikEval™.
This demonstration manual provides a quick start procedure, a DC2684A-B daughter card overview, a DC2683A mother board overview, schematics, and layout printouts.
ADI has always placed the highest emphasis on delivering products that meet the maximum levels of quality and reliability. We achieve this by incorporating quality and reliability checks in every scope of product and process design, and in the manufacturing process as well. "Zero defects" for shipped products is always our goal.
Sample & Buy
The USA list pricing shown is for BUDGETARY USE ONLY, shown in United States dollars (FOB USA per unit for the stated volume), and is subject to change. International prices may differ due to local duties, taxes, fees and exchange rates. For volume-specific price or delivery quotes, please contact your local Analog Devices, Inc. sales office or authorized distributor. Pricing displayed for Evaluation Boards and Kits is based on 1-piece pricing.