TPS65281, TPS65281-1

www.ti.com

SLVSBH7B – JULY 2012 – REVISED DECEMBER 2012

PRECISION ADJUSTABLE CURRENT LIMITED POWER DISTRIBUTION SWITCH WITH 4.5V

TO 18V INPUT VOLTAGE, 3A OUTPUT CURRENT SYNCHRONOUS BUCK REGULATOR

Check for Samples: TPS65281, TPS65281-1

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FEATURES

INTEGRATED POWER DISTRIBUTION SWITCH

INTEGRATED BUCK CONVERTER

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Wide Input Voltage Range: 4.5 V to 18 V

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Operating Input Voltage Range: 2.5 V to 6.5 V

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Maximum Continuous 3-A Output Current

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Adjustable Current Limit:

75 mA - 2.7 A (typical)

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Feedback Reference Voltage: 0.8 V ±1 %

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±6% Current-Limit Accuracy at 1.7 A (typical)

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Adjustable 300-kHz to 1.4-MHz Switching

Frequency

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Over Current Latch-Off Protection (TPS65281)

and Over Current Auto-Recovery (TPS65281-1)

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Adjustable Soft Start and Tracking With

Built-In 1-ms Internal Soft-Start Time

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Reverse Input-Output Voltage Protection

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Cycle-by-Cycle Current Limit

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Built-In Soft-Start

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Output Over-voltage Protection

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Integrated Back-to-Back Power MOSFETs With

100-m

Ω On-Resistance

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16-Lead QFN (RGV) 4-mm x 4-mm Package

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Over Temperature Protection

APPLICATIONS

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USB Ports and Hubs

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Digital TV

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Set-Top Boxes

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VOIP Phones

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Tablet PC

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xxx

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DESCRIPTION/ORDERING INFORMATION

The TPS65281/TPS65281-1 incorporates an N-channel back-to-back power MOSFET switch and a monolithic

buck converter. The device is intended to provide a total power distribution solution for digital TV, set-top boxes,

tablet PC and VOIP phones etc applications, where precision current limiting is required or heavy capacitive load

or short circuit are encountered.

A 100-m

Ω independent power distribution switch limits the output current to a programmable current limit

threshold between typical 75 mA and 2.7 A by using an external resistor. The current limit accauracy as tight as

±6% can be achieved at higher current limit setting. TPS65281 provides circuit breaker functionality by latching

off the power switch during over-current or reverse-voltage situations. TPS65281-1 limits output current to a safe

level by using a constant current mode when the output load exceeds the current limit threshold. An internal

reverse-voltage comparator disables the power switch when the output voltage is driven higher than the input to

protect the device on the input side of the switch in normal operation. The nFAULT output asserts low under

over-current and reverse-voltage conditions. Back-to-back power MOSFETs structure prevents the reverse

current injection from an active load at output port during shutdown of power switch.

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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 © 2012, 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.