LTC4447

1

4447f

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Integrated Schottky Diode

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38V Maximum Input Supply Voltage

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Adaptive Shoot-Through Protection

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Rail-to-Rail Output Drivers

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3.2A Peak Pull-Up Current

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4.5A Peak Pull-Down Current

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8ns TG Risetime Driving 3000pF Load

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7ns TG Falltime Driving 3000pF Load

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Separate Supply to Match PWM Controller

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Drives Dual N-Channel MOSFETs

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Undervoltage Lockout

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Low Profile (0.75mm) 3mm × 3mm DFN Package

TYPICAL APPLICATION

FEATURES

APPLICATIONS

DESCRIPTION

High Speed Synchronous

N-Channel MOSFET Driver

The LTC

ed bootstrap Schottky diode that is designed to drive two

N-Channel MOSFETs in a synchronous DC/DC converter.

The powerful rail-to-rail driver capability reduces switching

losses in MOSFETs with high gate capacitance.

The LTC4447 features a separate supply for the input logic

to match the signal swing of the controller IC. If the input

signal is not being driven, the LTC4447 activates a shut-

down mode that turns off both external MOSFETs. The input

logic signal is internally level-shifted to the bootstrapped

supply, which functions at up to 42V above ground. The

Schottky diode required for the bootstrapped supply is

integrated to simplify layout and reduce parts count.

The LTC4447 contains undervoltage lockout circuits on

both the driver and logic supplies that turn off the external

MOSFETs when an undervoltage condition is present. An

adaptive shoot-through protection feature is also built-in

to prevent the power loss resulting from MOSFET cross-

conduction current.

The LTC4447 is available in the 3mm × 3mm DFN

package.

Synchronous Buck Converter Driver

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Distributed Power Architectures

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High Density Power Modules

, LT, LTC and LTM are registered trademarks of Linear Technology Corporation. All

other trademarks are the property of their respective owners.

LTC4447 Driving 3000pF Capacitive Loads

TG

BOOST

TO 38V

GND

TS

LTC4447

BG

PWM

4V TO 6.5V

IN

4447 TA01a

TOP GATE

(TG - TS)

5V/DIV

INPUT (IN)

5V/DIV

4447 TA01b

BOTTOM GATE

(BG) 5V/DIV

10ns/DIV