LTC4371

1

4371f

For more information www.linear.com/LTC4371

Typical applicaTion

FeaTures

DescripTion

Dual Negative Voltage

Ideal Diode-OR Controller

and Monitor

The LTC®4371 is a two-input negative voltage ideal diode-OR

controller that drives external N-channel MOSFETs as a low

dissipation alternative to Schottky diodes in high power –48V

systems. Low power dissipation and voltage loss eliminates

the need for heatsinks and reduces PC board area. Power

sources can be easily ORed together to increase total system

power and reliability.

The LTC4371 tolerates ±300V transients such as those

experienced during lightning-induced surges and input

supply short-circuit events. The internal shunt regulator

and low 350μA quiescent current allow the use of a large

value dropping resistor to protect the supply pin against

high voltage transients, while the high impedance drain

pins can be similarly protected by high value series resis-

tors without compromising diode operation.

The 220ns reverse current turn-off is achieved by a powerful

2Agatedriverwithlowpropagationdelay,therebyminimizing

peakreversecurrentundercatastrophicfaultconditions.Open

MOSFETandfusefaultsareindicatedattheFAULTBpin,which

is capable of sinking 5mA to drive an LED or opto isolator.

applicaTions

n

Controls N-Channel MOSFETs to Replace Power

Schottky Diodes

n

Low 15mV Forward Voltage Minimizes Dissipation

n

Withstands > ±300V Transients

n

Fast Turn-Off: <220ns

n

Shunt Regulated for High Voltage Applications

n

4.5V Minimum Operation

n

Low 350μA Quiescent Current

n

5mA Gate Pull-Up for 60Hz Applications

n

High Impedance Drain Pins: <10μA Leakage

n

Open Fuse and MOSFET Monitor

n

10-Pin (3mm × 3mm) DFN and MSOP Packages

n

–48V Telecom Power

n

AdvancedTCA Systems

n

Network Routers and Switches

n

Computer Systems and Servers

L

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

Technology Corporation. All other trademarks are the property of their respective owners.

–48V/50A Diode-OR

Power Dissipation vs. Load Current

4371 TA01a

LTC4371

DA

DB

GB

GA

SA

FAULTB

C1

2.2F

20k

20k

M1*

M3*

M2*

–36V TO

–72V

–36V TO

–72V

50A LOAD

D1

GREEN LED =

MOSFETS GOOD

30k

R1

33k

RTN

M4*

*M1-M4: IPT020N10N3

MOSFET

(2–IPT020N10N3)

SCHOTTKY DIODE

(SBRT60U100CT)

POWER

SAVED

CURRENT (A)

0

10

20

30

40

50

0

10

20

30

40

vs Load Current

4371 TA01b