LTC4274A/LTC4274C - Single PoE/PoE+/LTPoE++ PSE Controller

The LTC®4274A is a single Power Sourcing Equipment (PSE) controller capable of delivering up to 90W of LTPoE++ power to a compatible LTPoE++ Powered Device (PD). A proprietary detection/classification scheme allows mutual identification between a LTPoE++ PSE and LTPoE++ PD while remaining compatible and interoperable with existing Type 1 (13W) and Type 2 (25.5W) PDs. The LTC4274A feature set is a superset of the popular LTC4274. These PSE controllers feature low-RON external MOSFETs and 0.25Ω sense resistors which are especially important at the LTPoE++ current levels to maintain the lowest possible heat dissipation.

The LTC4274C targets fully automatic PSE systems powering Type 1 (up to 13W) PDs.

Advanced power management features include: a 14-bit current monitoring ADC, DAC-programmable current limit, and versatile quick port shutdown. PD Discovery uses a proprietary dual-mode 4-point detection mechanism ensuring excellent immunity from false PD detection. The LTC4274A/LTC4274C includes an I2C serial interface operable up to 1MHz.

The LTC4274A/LTC4274C is available in multiple power grades, allowing delivered PD power of 13W, 25.5W, 38.7W, 52.7W, 70W and 90W. These controllers are available in a 38-lead 5mm × 7mm QFN package.

  • Compliant with IEEE 802.3at Type 1 and 2
  • Low Power Dissipation
  • 0.25Ω Sense Resistance Per Channel
  • Very High Reliability 4-Point PD Detection
  • 2-Point Forced Voltage
  • 2-Point Forced Current
  • High Capacitance Legacy Device Detection
  • 1MHz I2C Compatible Serial Control Interface
  • Midspan Backoff Timer
  • Supports 2-Pair and 4-Pair Output Power
  • Available in Multiple Power Grades
  • LTC4274A-1: LTPoE++™ 38.7W
  • LTC4274A-2: LTPoE++ 52.7W
  • LTC4274A-3: LTPoE++ 70W
  • LTC4274A-4: LTPoE++ 90W
  • LTC4274C: PoE 13W
  • Available in 38-Lead 5mm × 7mm QFN Package
Typical Application
  • LTPoE++ PSE Switches/Routers
  • LTPoE++ PSE Midspans
  • IEEE 802.3at Type 1 PSE Switches/Routers
  • IEEE 802.3at Type 1 PSE Midspans
Order Information
Part NumberPackageTempPrice(1-99)Price (1k)*
LTC4274AIUHF-1#PBF5x7 QFN-38I$7.71$5.40
LTC4274AIUHF-1#TRPBF5x7 QFN-38I$5.46
LTC4274AIUHF-2#PBF5x7 QFN-38I$7.71$5.40
LTC4274AIUHF-2#TRPBF5x7 QFN-38I$5.46
LTC4274AIUHF-3#PBF5x7 QFN-38I$7.71$5.40
LTC4274AIUHF-3#TRPBF5x7 QFN-38I$5.46
LTC4274AIUHF-4#PBF5x7 QFN-38I$7.71$5.40
LTC4274AIUHF-4#TRPBF5x7 QFN-38I$5.46
LTC4274CIUHF#PBF5x7 QFN-38I$6.43$4.50
LTC4274CIUHF#TRPBF5x7 QFN-38I$4.56
Demo Boards
Part NumberDescriptionPrice
DC1814A-ALTC4274A-1 Demo Board | LTPoE++ (38.7W) PSE$100.00
DC1814A-BLTC4274A-2 Demo Board | LTPoE++ (52.7W) PSE$100.00
DC1814A-CLTC4274A-3 Demo Board | LTPoE++ (70W) PSE$100.00
DC1814A-DLTC4274A-4 Demo Board | LTPoE++ (90W) PSE$100.00
Companion Boards
Part NumberDescriptionPrice
DC2046A-ELT4276A/LT4321 Demo Board | LTPoE++ (38.7W, 5V/7A) PD with DC/DC and Ideal Diode Bridge$95.00
DC2093A-ALT4275A/LT4321 LTPoE++/PoE+/PoE PD Demo Board$95.00
DC2262A-ALT4276A/LT4321 Demo Board | LTPoE++ (70W, 5V/13A) PD with DC/DC and Ideal Diode Bridge$95.00
DC2262A-BLT4276A/LT4321 Demo Board | LTPoE++ (90W, 12V/7A) PD with DC/DC and Ideal Diode Bridge$95.00
Reliability Data
Product Selector Card
Press Release
Related Product
LTC4274A/LTC4274C - Single PoE/PoE+/LTPoE++ PSE Controller
R547 - Reliability Data
LTPoE++ PSE Controllers
PoE PD Controllers
Power over Ethernet Solutions
四端口和单端口 LTPoE++ PSE 控制器提供高达 90W
LTC4274A_C Footprints and Symbols