LTC4274

1

4274fa

APPLICATIONS

FEATURES

DESCRIPTION

Single PoE+ PSE Controller

troller 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 LTC4274 includes advanced power management

features, including current and voltage readback and pro-

simplify 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.

The LTC4274 is available in a 5mm × 7mm QFN package

that significantly reduces board space compared with

competing solutions.

130mW/Port at 600mA

Fast Shutdown

14.5-Bit Port Current/Voltage Monitoring

2-Event Classification

2-Point Forced Voltage

2-Point Forced Current

TYPICAL APPLICATION

Complete Ethernet High Power Source

L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and

ThinSOT is a trademark of Linear Technology Corporation. All other trademarks are the property

of their respective owners.

4274 TA01

SCL

SDAIN

SDAOUT

AD0

AD1

AD2

AD3

AGND

–54V

1μF

100V

SMAJ58A

GATE

OUT

PORT

0.22μF

100V

S1B

S1B

–54V

DGND

INT

SHDN

AUTO

MSD

RESET

MID

0.1μF

3.3V

LTC4274