LTC4266
PRODUCTIONQuad IEEE 802.3at Power Over Ethernet Controller
- Part Models
- 8
- 1ku List Price
- Starting From $7.54
Overview
- Four Independent PSE Channels
- Compliant with IEEE 802.3at Type 1 and 2
- 0.34Ω Total Channel Resistance
- 130mW/Port at 600mA
- Advanced Power Management
- 8-Bit Programmable Current Limit (ILIM)
- 7-Bit Programmable Overload Currents (ICUT)
- Fast Shutdown of Preselected Ports
- 14.5-Bit Port Current/Voltage Monitoring
- 2-Event Classification
- Very High Reliability 4-Point PD Detection
- 2-Point Forced Voltage
- 2-Point Forced Current
- High Capacitance Legacy Device Detection
- LTC4259A-1 and LTC4258 Pin and SW Compatible
- 1MHz I2C Compatible Serial Control Interface
- Midspan Backoff Timer
- Supports Proprietary Power Levels Above 25W
- Available in 38-Pin 5mm × 7mm QFN and 36-Pin SSOP Packages
The LTC4266 is a quad PSE controller designed for use in IEEE 802.3 Type 1 and Type 2 (high power) compliant Power over Ethernet systems. External power MOSFETs enhance system reliability and minimize channel resistance, cutting power dissipation and eliminating the need for heatsinks even at Type 2 power levels. External power components also allow use at very high power levels while remaining otherwise compatible with the IEEE standard. 80V-rated port pins provide robust protection against external faults.
The LTC4266 includes advanced power management features, including current and voltage readback and programmable ICUT and ILIM thresholds. Available C libraries simplify power-management software development; an optional AUTO pin mode provides fully IEEE-compliant standalone operation with no software required. Proprietary 4-point PD detection circuitry minimizes false PD detection while supporting legacy phone operation. Midspan operation is supported with built-in 2-event classification and backoff timing. Host communication is via a 1MHz I2C serial interface.
The LTC4266 is available in a 5mm × 7mm QFN package that significantly reduces board space compared with competing solutions. A legacy-compatible 36-pin SSOP package is also available.
Applications
- High Power PSE Switches/Routers
- High Power PSE Midspans
Documentation
Data Sheet 1
User Guide 1
Technical Articles 2
Video 2
Product Selector Card 4
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. View our quality and reliability program and certifications for more information.
| Part Model | Pin/Package Drawing | Documentation | CAD Symbols, Footprints, and 3D Models |
|---|---|---|---|
| LTC4266CGW#PBF | 36-Lead SSOP (Wide 0.3 Inch) | ||
| LTC4266CGW#TRPBF | 36-Lead SSOP (Wide 0.3 Inch) | ||
| LTC4266CUHF#PBF | 38-Lead QFN (5mm x 7mm w/ EP) | ||
| LTC4266CUHF#TRPBF | 38-Lead QFN (5mm x 7mm w/ EP) | ||
| LTC4266IGW#PBF | 36-Lead SSOP (Wide 0.3 Inch) | ||
| LTC4266IGW#TRPBF | 36-Lead SSOP (Wide 0.3 Inch) | ||
| LTC4266IUHF#PBF | 38-Lead QFN (5mm x 7mm w/ EP) | ||
| LTC4266IUHF#TRPBF | 38-Lead QFN (5mm x 7mm w/ EP) |
| Part Models | Product Lifecycle | PCN |
|---|---|---|
|
Feb 14, 2025 - 25_0017 Bond Wire Change from Gold to Copper |
||
| LTC4266CGW#PBF | PRODUCTION | |
| LTC4266CGW#TRPBF | PRODUCTION | |
| LTC4266CUHF#PBF | PRODUCTION | |
| LTC4266CUHF#TRPBF | PRODUCTION | |
|
Aug 10, 2022 - 22_0174 Laser Top Mark Conversion for SSOP_W Package Assembled in ADPG [PNG] |
||
| LTC4266CGW#PBF | PRODUCTION | |
| LTC4266CGW#TRPBF | PRODUCTION | |
| LTC4266IGW#PBF | PRODUCTION | |
| LTC4266IGW#TRPBF | PRODUCTION | |
|
Nov 8, 2021 - 20_0245 Notification of Wafer Fab Location Change for 0.6µm BICMOS Process Devices from ADI Milpitas (Hillview) to Vanguard Int. (Taiwan) |
||
| LTC4266CGW#PBF | PRODUCTION | |
| LTC4266CGW#TRPBF | PRODUCTION | |
| LTC4266CUHF#PBF | PRODUCTION | |
| LTC4266CUHF#TRPBF | PRODUCTION | |
| LTC4266IGW#PBF | PRODUCTION | |
| LTC4266IGW#TRPBF | PRODUCTION | |
| LTC4266IUHF#PBF | PRODUCTION | |
| LTC4266IUHF#TRPBF | PRODUCTION | |
This is the most up-to-date revision of the Data Sheet.
Software Resources
Evaluation Software 1
Software Interface Data Sheet and Software
The software interface data sheet for this PSE may be requested from the Software Request Form (SRF). This data sheet describes the I2C interface and programming details for the respective PSE controller.
Reference software for IEEE 802.3at Semi-auto mode operation is available for this PSE controller and may be requested from the Software Request Form.
Can't find the software or driver you need?
Hardware Ecosystem
| Parts | Product Life Cycle | Description |
|---|---|---|
| Hot Swap Controllers 1 | ||
| LT4363 | RECOMMENDED FOR NEW DESIGNS | High Voltage Surge Stopper with Current Limit |
| Interface Transceivers 1 | ||
| LTM2883 | PRODUCTION | SPI/Digital or I2C μModule Isolator with Adjustable ±12.5V and 5V Regulated Power |
| Power-over-Ethernet (PoE) Controllers 2 | ||
| LTC4266A/LTC4266C | Quad PoE/PoE+/LTPoE++ PSE Controller | |
| LTC4270 | PRODUCTION | 12-Port PoE/PoE+/LTPoE++ PSE Analog Controller |
Evaluation Kits
LTC4266 Demo Board | 25.5W PoE + 4-Port Midspan PSE (Requires DC590)