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

LTC4266 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

LTC4266 Package Drawing
LTC4266 Package Drawing

Order Info

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
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* 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 Linear Technology sales office or authorized distributor.

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
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Companion Boards

Part Number Description Price Documentation
DC590B USB Serial Controller for Linear Technology QuikEval Demo Boards $50.00
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Click here to view our complete list of demo boards

Applications

  • High Power PSE Switches/Routers
  • High Power PSE Midspans

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