LT4321

12

4321f

For more information www.linear.com/LT4321



LINEAR TECHNOLOGY CORPORATION 2013

LT 0913 • PRINTED IN USA

LinearTechnology Corporation

1630 McCarthy Blvd., Milpitas, CA 95035-7417

relaTeD parTs

PART NUMBER

DESCRIPTION

COMMENTS

LTC4265

IEEE 802.3at PD Interface Controller

Internal 100V, 1A Switch, 2-Event Classification Recognition

LTC4266/LTC4266A/

LTC4266C

Quad PoE PSE Controller

IEEE 802.3at, LTPoE++, IEEE 802.3af Power Levels

LTC4269-1/

LTC4269-2

IEEE 802.3af PD Interface with

Switching Regulator

LTC4269-1 for Flyback, LTC4269-2 for Forward Regulator

LTC4270/LTC4271

12-Port PoE/PoE+/LTPoE++ PSE

Controller

Transformer Isolation, Supports IEEE 802.3af, IEEE 802.3at and LTPoE++ PDs

LTC4274/LTC4274A/

LTC4274C

Single PoE PSE Controller

IEEE 802.3at, LTPoE++ 90W, IEEE 802.3af Power Levels

LT4275A/LT4275B/

LT4275C

LTPoE++/PoE+/PoE PD Controller

External Switch, LTPoE++ Support

LTC4278

IEEE 802.3af PD Interface with

Integrated Flyback Switching

Regulator

2-Event Classification, Programmable Class, Synchronous No-Opto Flyback Controller,

50kHz to 250kHz, 12V Aux Support

LTC4290/LTC4271

8-Port PoE/PoE+/LTPoE++ PSE

Controller

Transformer Isolation, Supports IEEE 802.3af, IEEE 802.3at and LTPoE++ PDs

LT4320

Ideal Diode Bridge Controller

9V to 72V, DC to 600Hz, N-Channel Ideal Diode Bridge

LTC4354

Negative Voltage Diode-OR Controller

and Monitor

Controls Two N-Channel MOSFETs, 1.2µs Turn-Off, –80V Operation

LTC4355

Positive Voltage Diode-OR Controller

and Monitor

Controls Two N-Channel MOSFETs, 0.4µs Turn-Off, 9V to 80V Operation

LTC4359

Ideal Diode Controller with Reverse

Input Protection

N-Channel, 4V to 80V, MSOP-8 and DFN-6 Packages

Typical applicaTion

LTPoE++ 70W Powered Device

4321 TA03

LT4321

TG36

BG12

PSMN075-100MSE ×4

PSMN075-100MSE ×4

WÜRTH 749022016

BG36

IN36

IN45

IN78

IN12

DATA

PAIRS

1

2

3

6

4

5

8

7

SPARE

PAIRS

OUTN

EN

OUTP

SMAJ60A

VPORT

PWRGD

AUX

IEEEUVLO

RCLASS

RCLASS++

HSGATE

PSMN040-100MSE

LT4275

GND

EN

TG12

BG78

TG45

TG78

BG45

HSSRC

ISOLATED

POWER

SUPPLY

GND

RUN

0.1µF

22µF

–

+

76.8

64.9

+

47nF

3.3k

100k