
SLVSAW8
– JUNE 2011
4.5-V TO 16-V INPUT, HIGH CURRENT, SYNCHRONOUS STEP DOWN DUAL BUCK
CONVERTER WITH INTEGRATED FETS
Current-Mode Control With Simple
1
FEATURES
Compensation Circuit
Wide Input Supply Voltage Range:
Power Good and Reset Generator
4.5 V - 16 V
Low Power Mode Set By External Signal
Output Range: 0.8 V to ~VIN-1 V
Supervisory Circuit
Fully Integrated Dual Buck, 3.5-A/2.5-A
QFN Package, 28-Pin 5 mm x 5 mm RHD
Continuous Current (4-A/3-A Maximum
Current)
APPLICATIONS
High Efficiency
300-kHz - 1.2-MHz Switching Frequency Set by
DTV
External Resistor
DSL Modems
External Eenable/Sequencing Pins
Cable Modems
Adjustable Cycle-by-Cycle Current Limit Set
Set Top Boxes
by External Resistor
Car DVD Players
Soft-Start Pins
Home Gateway and Access Point Networks
Wireless Routers
DESCRIPTION/ORDERING INFORMATION
The TPS65253 features two synchronous wide input range high efficiency buck converters. The converters are
designed to simplify product application while giving designers the options to optimize their usage according to
the target application.
The converters can operate in 5-, 9- and 12-V systems and have integrated power transistors. The output voltage
can be set externally using a resistor divider to any value between 0.8 V and the input supply minus 1 V. Each
converter features an enable pin that allows a delayed start-up for sequencing purposes, soft-start pin that allows
adjustable soft-start time by choosing the soft-start capacitor, and a current limit (RLIMx) pin that enables
designer to adjust current limit by selecting an external resistor and optimize the choice of inductor. The CMP pin
allows optimizing transient versus dc accuracy response with a simple RC compensation.
The switching frequency of the converters is set by an external resistor connected to ROSC pin. The switching
regulators are designed to operate from 300 kHz to 1.2 MHz. The converters operate with 180
° phase between
then to minimize the input filter requirements.
TPS65253 also features a low power mode enabled by an external signal, which allows for a reduction on the
input power supplied to the system when the host processor is in stand-by (low activity) mode.
TPS65253 features a supervisor circuit that monitors both converters and provides a PGOOD signal (End of
Reset) with a 32-ms timer.
TPS65253 is packaged in a small, thermally efficient 28-pin QFN package.
ORDERING INFORMATION(1)
TA
PACKAGE(2)
PART NUMBER
TOP-SIDE MARKING
-40
°C to 85°C
28-Pin (QFN) - RHD
TPS65253RHD
TPS65253
(1)
For the most current packaging and ordering information, see the Package Option Addendum at the end of this document, or see the TI
(2)
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.
Copyright
2011, 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.