TPS65282 Datasheet, PDF (1/36 Pages) Texas Instruments – DUAL POWER DISTRIBUTION SWITCHES WITH 4.5-V to 18-V INPUT VOLTAGE, 4-A OUTPUT CURRENT SYNCHRONOUS BUCK REGULATOR

TPS65282
www.ti.com
SLVSBU5 – MARCH 2013
DUAL POWER DISTRIBUTION SWITCHES WITH 4.5-V to 18-V INPUT VOLTAGE,
4-A OUTPUT CURRENT SYNCHRONOUS BUCK REGULATOR
Check for Samples: TPS65282
FEATURES
1
INTEGRATED POWER DISTRIBUTION SWITCH
• Operating Input Voltage Range: 2.5 V to 6.5 V
• Integrated Back-to-Back Power MOSFETs With
100-mΩ On-Resistance
• Adjustable Current Limit:
75 mA - 2.7 A (typical)
• ±6% Current-Limit Accuracy at 1.7 A (typical)
• Latch-Off Over Current Protection Versions
• Reverse Input-Output Voltage Protection
• Built-In Soft-Start
• 4-kV HBM and 200-V MM ESD Protection at
Power Switch Output Pins
xxx
INTEGRATED BUCK DC/DC CONVERTER
• Wide Input Voltage Range: 4.5 V to 18 V
• Maximum Continuous 4-A Output Current
• Feedback Reference Voltage: 0.8 V ±1 %
• Adjustable 300-kHz to 1.4-MHz Switching
Frequency
• Pulse Skipping Mode at Light Load Efficiency
• Adjustable Soft-Start and Tracking With
Built-In 1.2-ms Internal Soft-Start Time
• Cycle-by-Cycle Current Limit
• Output Over-Voltage Protection
• Power Good Indicator
• Over Temperature Protection
• 24-Lead QFN (RGE) 4-mm x 4-mm Package
APPLICATIONS
• USB Ports and Hubs
• Digital TV
• Set-Top Boxes
• VOIP Phones
• Tablet PC
DESCRIPTION
The TPS65282 incorporates dual N-channel MOSFET power switches for USB power distribution systems that
require dual power switches in a single package. It also integrates a buck monolithic converter. The device is
intended to provide a total USB 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 loads or short circuits are
encountered.
Dual 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 accuracy can be
achieved as tight as ±6% at higher current limit setting. TPS65282 device limits output current to a safe level by
using a constant current mode when output load exceeds the current limit threshold. After deglitching time,
TPS65282 provides circuit breaker functionality by latching off the power switch during over-current or reverse-
voltage situations. Two back-to-back power MOSFETs prevents the current injects from output to input in
shutdown. An internal reverse-voltage comparator disables the power switch when the output voltage is driven
higher than the input to protect the circuits on the input side of the switch in normal operation. The nFAULT1/2
output asserts low during over-current and reverse-voltage conditions.
The buck DC/DC converter integrates power MOSFETs for optimized power efficiency and reduced external
component. A wide 4.5-V to 18-V input supply range to buck encompasses most intermediate bus voltages
operating off 5-V, 9-V, 12-V or 15-V power bus. Peak current mode control simplifies the compensation and fast
transient response. Equipped with enable and soft-start pin, the DC/DC can be precisely sequenced and ramp up
in order to align with other rails in the system. Cycle-by-cycle over-current protection and operating in hiccup
mode limit MOSFET power dissipation during buck output short circuit or over loading fault conditions. The
switching frequency of the converter can be programmed from 300 kHz to 1.4 MHz with an external resistor at
ROSC pin. With ROSC pin connecting to V7V pin, floating, or grounding, a default fixed switching frequency can
be selected. The buck also features a pulse skipping mode (PSM), which allows a power loss reduction on the
input power supplied to the system to achieve high efficiency at light loading.
1
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 © 2013, Texas Instruments Incorporated