TPS65281_15 Datasheet, PDF (1/34 Pages) Texas Instruments – PRECISION ADJUSTABLE CURRENT LIMITED POWER DISTRIBUTION SWITCH WITH 4.5V TO 18V INPUT VOLTAGE, 3A OUTPUT CURRENT SYNCHRONOUS BUCK REGULATOR

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
FEATURES
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INTEGRATED POWER DISTRIBUTION SWITCH
• Operating Input Voltage Range: 2.5 V to 6.5 V
• Adjustable Current Limit:
75 mA - 2.7 A (typical)
• ±6% Current-Limit Accuracy at 1.7 A (typical)
• Over Current Latch-Off Protection (TPS65281)
and Over Current Auto-Recovery (TPS65281-1)
• Reverse Input-Output Voltage Protection
• Built-In Soft-Start
• Integrated Back-to-Back Power MOSFETs With
100-mΩ On-Resistance
• Over Temperature Protection
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INTEGRATED BUCK CONVERTER
• Wide Input Voltage Range: 4.5 V to 18 V
• Maximum Continuous 3-A Output Current
• Feedback Reference Voltage: 0.8 V ±1 %
• Adjustable 300-kHz to 1.4-MHz Switching
Frequency
• Adjustable Soft Start and Tracking With
Built-In 1-ms Internal Soft-Start Time
• Cycle-by-Cycle Current Limit
• Output Over-voltage Protection
• 16-Lead QFN (RGV) 4-mm x 4-mm Package
APPLICATIONS
• USB Ports and Hubs
• Digital TV
• Set-Top Boxes
• VOIP Phones
• Tablet PC
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-mΩ 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.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
Copyright © 2012, Texas Instruments Incorporated