LTC4266 - Quad IEEE 802.3at Power Over Ethernet Controller
Features
- 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
Typical Application
Description
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 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.
Packaging
For complete and up to date package information and drawings, please refer to our packaging page
QFN-38,SSOP-36
Order Info
- Part numbers ending in PBF are lead free. Please contact LTC marketing for information on lead based finish parts.
- Part numbers containing TR or TRM are shipped in tape and reel or 500 unit mini tape and reel, respectively
- Please refer to our general ordering information or the product datasheet for more details
Package Variations and Pricing
| Part Number | Package | Pins | Temp | Price (1-99) | Price (1k)* | RoHS Data |
|---|---|---|---|---|---|---|
| LTC4266AIUHF-1#PBF | QFN | 38 | I | $8.57 | $6.00 | View |
| LTC4266AIUHF-1#TRPBF | QFN | 38 | I | $6.06 | View | |
| LTC4266AIUHF-2#PBF | QFN | 38 | I | $8.57 | $6.00 | View |
| LTC4266AIUHF-2#TRPBF | QFN | 38 | I | $6.06 | View | |
| LTC4266AIUHF-3#PBF | QFN | 38 | I | $8.57 | $6.00 | View |
| LTC4266AIUHF-3#TRPBF | QFN | 38 | I | $6.06 | View | |
| LTC4266AIUHF-4#PBF | QFN | 38 | I | $8.57 | $6.00 | View |
| LTC4266AIUHF-4#TRPBF | QFN | 38 | I | $6.06 | View | |
| LTC4266CGW#PBF | SSOP | 36 | C | $7.14 | $5.00 | View |
| LTC4266CGW#TRPBF | SSOP | 36 | C | $5.06 | View | |
| LTC4266CIUHF#PBF | QFN | 38 | I | $7.14 | $5.00 | View |
| LTC4266CIUHF#TRPBF | QFN | 38 | I | $5.06 | View | |
| LTC4266CUHF#PBF | QFN | 38 | C | $7.14 | $5.00 | View |
| LTC4266CUHF#TRPBF | QFN | 38 | C | $5.06 | View | |
| LTC4266IGW#PBF | SSOP | 36 | I | $7.86 | $5.50 | View |
| LTC4266IGW#TRPBF | SSOP | 36 | I | $5.56 | View | |
| LTC4266IUHF#PBF | QFN | 38 | I | $7.86 | $5.50 | View |
| LTC4266IUHF#TRPBF | QFN | 38 | I | $5.56 | View | |
| Buy Now • Request Samples | ||||||
Demo Boards
Linear Technology offers many demo boards free of charge to qualified customers. Contact your local sales office or distributor to inquire about a demo board. Certain demo boards are also available for sale via credit card on this website. Demo boards are for evaluation purposes only. It remains the customer’s responsibility to verify proper and reliable operation in the actual end application.| Part Number | Description | Price | Documentation |
|---|---|---|---|
| DC1366A | LTC4266: 25.5W PoE+ 4-Port Midspan PSE (req. DC590) | $200.00 | |
| DC1420A | (12-port) LTC4266 IEEE802.3at Quad Powered Ethernet PSE (no ICM, req. DC590) | Contact Factory | |
| DC1581A | (8-port) LTC4266 IEEE802.3at Quad Powered Ethernet PSE (no ICM, req DC590) | Contact Factory | |
| Buy Now | |||
Companion Boards
| Part Number | Description | Price | Documentation |
|---|---|---|---|
| DC590B | USB Serial Controller for Linear Technology QuikEval Demo Boards | $50.00 | |
| Buy Now | |||
Applications
- High Power PSE Switches/Routers
- High Power PSE Midspans
People Who Viewed This Product Also Viewed
- LT4363 - High Voltage Surge Stopper with Current Limit
- LTC4266A/LTC4266C - Quad PoE/PoE+/LTPoE++ PSE Controller
- LTC4263 - Single IEEE 802.3af Compliant PSE Controller with Internal Switch
- LTC4274 - Single IEEE 802.3at Power Over Ethernet Controller
- LTC4274A/LTC4274C - Single PoE/PoE+/LTPoE++ PSE Controller
- LT4275 - LTPoE++/PoE+/PoE PD Controller
- LT4356-1 and -2 - Surge Stopper
- LTC4270/LTC4271 - 12-Port PoE/PoE+/LTPoE++ PSE Controller
- LTM2883 - SPI/Digital or I2C μModule Isolator with Adjustable ±12.5V and 5V Regulated Power
- LTC4364 - Surge Stopper with Ideal Diode
Product Notifications
Please login to your MyLinear account for notifications of datasheet updates, new document releases and LTspice model announcements for your favorite products. If you do not have a MyLinear account you may Sign Up Now.
Forgot your password? Click here.
Need help? Email mylinear@linear.com with questions and comments.
Simulate
LTspice IV is a powerful, fast and free simulation tool, schematic capture and waveform viewer with enhancements and models for improving the simulation of switching regulators. To download LTspice IV and other FREE simulation tools, please visit our Design Simulation page.
Technical Support
- For immediate technical assistance, contact your local sales office or distributor or call 1-800-4-LINEAR (US customers only) or 408-432-1900.
- For less urgent requests, please complete our Technical Support Request Form. Please allow 2-3 business days for reply.
