LM3544

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SNVS062C – AUGUST 2000 – REVISED MAY 2013

Check for Samples: LM3544

1

FEATURES

DESCRIPTION

The LM3544 is a quad high-side power switch that is

•

Compatible with USB1.1 and USB 2.0

an excellent choice for use in Root, Self-Powered and

•

90m

Ω (typ.) High-Side MOSFET Switch

Bus- Powered USB (Universal Serial Bus) Hubs.

•

500mA Continuous Current per Port

Independent port enables, flag signals to alert USB

controllers of error conditions, controlled start-up in

•

7 ms Fault Flag Delay Filters Hot-Plug Events

hot-plug events, and short circuit protection all satisfy

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Industry Standard Pin Order

USB requirements.

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Short Circuit Protection with Power-Saving

The LM3544 accepts input voltages between 2.7V

Current Foldback

and 5.5V. The Enable logic inputs, available in active-

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Thermal Shutdown Protection

high and active-low versions, can be powered off any

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Undervoltage Lockout

voltage in the 2.7V to 5.5V range. The LM3544 limits

the continuous current through a single port to 1.25A

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Recognized by UL and Nemko CB

(max.) when it is shorted to ground.

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Input Voltage Range: 2.7V to 5.5V

The low on-state resistance of the LM3544 switches

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5

μA Maximum Standby Supply Current

ensures the LM3544 will satisfy USB voltage drop

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16-Pin SOIC Package

requirements, even when current through a switch

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Ambient Temperature Range:

−40°C to 85°C

reaches

500

mA.

Thus,

High-Powered

USB

Functions, Low-Powered USB functions, and Bus-

Powered USB Hubs can all be powered off a Root or

APPLICATIONS

Self-Powered USB Hub containing the LM3544.

•

USB Root, Self-Powered, and Bus-Powered

Added features of the LM3544 include current fold-

Hubs

back

to

reduce

power

consumption

in

current

•

USB Devices such as Monitors and Printers

overload conditions, thermal shutdown to prevent

•

General Purpose High Side Switch

device failure caused by high current overheating,

Applications

and undervoltage lockout to keep switches from

operating if the input voltage is below acceptable

levels.

Functional Diagram

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Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of

Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.

PRODUCTION DATA information is current as of publication date.

Copyright © 2000–2013, Texas Instruments Incorporated

Products conform to specifications per the terms of the Texas

Instruments standard warranty. Production processing does not

necessarily include testing of all parameters.