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LTC1155

Dual High Side

Micropower MOSFET Driver

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FEATURE

APPLICATI

TYPICAL

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Fully Enhances N-Channel Power MOSFETs

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8

µA Standby Current

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85

µA ON Current

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Short-Circuit Protection

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Wide Power Supply Range: 4.5V to 18V

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Controlled Switching ON and OFF Times

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No External Charge Pump Components

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Replaces P-Channel High Side MOSFETs

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Compatible with Standard Logic Families

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Available in 8-Pin SO Package

DESCRIPTIO

The LTC

cost N-channel FETs for high side switching applications.

An internal charge pump boosts the gate above the posi-

tive rail, fully enhancing an N-channel MOSFET with no

external components. Micropower operation, with 8

µA

standby current and 85

µA operating current, allows use in

virtually all systems with maximum efficiency.

Included on-chip is overcurrent sensing to provide auto-

matic shutdown in case of short circuits. A time delay can

be added in series with the current sense to prevent false

triggering on high in-rush loads such as capacitors and

incandescent lamps.

The LTC1155 operates off of a 4.5V to 18V supply input

and safely drives the gates of virtually all FETs. The

LTC1155 is well suited for low voltage (battery-powered)

applications, particularly where micropower “sleep” op-

eration is required.

The LTC1155 is available in both 8-pin PDIP and 8-pin SO

packages.

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

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APPLICATI

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Laptop Power Bus Switching

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SCSI Termination Power Switching

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Cellular Phone Power Management

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P-Channel Switch Replacement

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Relay and Solenoid Drivers

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Low Frequency Half H-Bridge

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Motor Speed and Torque Control

OUTPUT CURRENT (A)

0

0.00

0.05

0.10

0.15

0.20

0.25

12

3

1155 TA02

Switch Voltage Drop

1155 TA01

0.02

Ω

0.1

µF

10

µF

5A

MAX

100k

POWER BUS

µP

SYSTEM

DISK

DRIVE

DISPLAY

PRINTER,

ETC.

LTC1155

TTL, CMOS INPUT

TTL, CMOS INPUT

GND

GND

IN1

IN2

G2

DS2

DS1

G1

0.1

µF

0.02

Ω

100k

*SURFACE MOUNT

*IRLR034

5A

MAX

*IRLR034

+

Laptop Computer Power Bus Switch with Short Circuit Protection