LTC4446

1

4446f

TYPICAL APPLICATION

FEATURES

APPLICATIONS

DESCRIPTION

High Voltage High Side/

Low Side N-Channel

MOSFET Driver

The LTC

that drives two N-channel MOSFETs in a DC/DC converter

with supply voltages up to 100V. The powerful driver ca-

pability reduces switching losses in MOSFETs with high

gate capacitance. The LTC4446’s pull-up for the top gate

driver has a peak output current of 2.5A and its pull-down

has an output impedance of 1.2

Ω. The pull-up for the bot-

tom gate driver has a peak output current of 3A and the

pull-down has an output impedance of 0.55

Ω.

The LTC4446 is configured for two supply-independent

inputs. The high side input logic signal is internally

level-shifted to the bootstrapped supply, which may

function at up to 114V above ground.

The LTC4446 contains undervoltage lockout circuits that

disable the external MOSFETs when activated.

The LTC4446 is available in the thermally enhanced 8-lead

MSOP package.

The LTC4446 does not have adaptive shoot-through pro-

tection. For similar drivers with adaptive shoot-through

protection, please refer to the chart below.

PARAMETER

LTC4446

LTC4444

LTC4444-5

Shoot-Through Protection

No

Yes

Yes

Absolute Max TS

100V

100V

100V

MOSFET Gate Drive

7.2V to 13.5V 7.2V to 13.5V 4.5V to 13.5V

6.6V

6.6V

4V

6.15V

6.15V

3.55V

Ω Top Gate Driver Pull-Down

Ω Bottom Gate Driver Pull-Down

Two Switch Forward Converter

LTC4446 Driving a 1000pF Capacitive Load

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

All other trademarks are the property of their respective owners.

Protected by U.S. Patents including 6677210.

TG

BOOST

36V TO 72V

(100V ABS MAX)

GND

TS

TO

SECONDARY

CIRCUIT

•

TINP

LTC4446

BG

PWM2

(FROM CONTROLLER IC)

PWM1

(FROM CONTROLLER IC)

7.2V TO 13.5V

BINP

4446 TA01a

•

BINP

5V/DIV

BG

10V/DIV

TINP

5V/DIV

TG-TS

10V/DIV

20ns/DIV

4446 TA01b