TPS54317 Datasheet, PDF (1/17 Pages) Texas Instruments – 1.6 MHz, 3-V TO 6-V INPUT, 3-A SYNCHRONOUS STEP-DOWN SWIFT CONVERTER

TPS54317
www.ti.com
SLVS619A – NOVEMBER 2005 – REVISED FEBRUARY 2006
1.6 MHz, 3-V TO 6-V INPUT, 3-A SYNCHRONOUS STEP-DOWN SWIFT™ CONVERTER
FEATURES
• 60-mΩ MOSFET Switches for High Efficiency
at 3-A Continuous Output Current
• Adjustable Output Voltage Down to 0.9 V With
1% Accuracy
• Switching Frequency: Adjustable From
280 kHz to 1600 kHz
• Externally Compensated for Design Flexibility
• Fast Transient Response
• Load Protected by Peak Current Limit and
Thermal Shutdown
• Integrated Solution Reduces Board Area and
Total Cost
• Spacing Saving 4mm x 5mm QFN Packaging
• For SWIFT Documentation, Application Notes,
and Design Software, see the TI website at
www.ti.com/swift
APPLICATIONS
• Low-Voltage, High-Density Systems With
Power Distributed at 5 V or 3.3 V
• Point of Load Regulation for High
Performance DSPs, FPGAs, ASICs, and
Microprocessors
• Broadband, Networking and Optical
Communications Infrastructure
Input
Simplified Schematic
TPS54317
VIN
PH
PWRGD
SS/ENA
SYNC
RT
VBIAS
BOOT
PGND
VSENSE
AGND COMP
DESCRIPTION
As members of the SWIFT™ family of dc/dc
regulators, the TPS54317 low-input-voltage
high-output-current synchronous-buck PWM
converter integrates all required active components.
Included on the substrate with the listed features are
a true, high performance, voltage error amplifier that
provides high performance under transient conditions;
an undervoltage-lockout circuit to prevent start-up
until the input voltage reaches 3 V; an internally and
externally set slow-start circuit to limit in-rush
currents; and a power good output useful for
processor/logic reset, fault signaling, and supply
sequencing.
The TPS54317 device is available in a thermally
enhanced 24-pin QFN (RHF) PowerPAD™ package,
which eliminates bulky heatsinks. TI provides
evaluation modules and the SWIFT designer software
tool to aid in achieving high-performance power
supply designs to meet aggressive equipment
development cycles.
Output
EFFICIENCY
vs
LOAD CURRENT
100
95
90
85
80
75
70
65
T_A = 25^oC,
60 ^VI ^{= 3.3 V,}
55
V_O = 1.8 V,
fs = 1.1 MHz
50
0 0.5
1 1.5
2 2.5
3 3.5
I_O - Output Current − A
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.
SWIFT, PowerPAD are trademarks of Texas Instruments.
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 © 2005–2006, Texas Instruments Incorporated