TPS54377 Datasheet, PDF (1/21 Pages) Texas Instruments – 1.6 MHz, 3-V TO 6-V INPUT, 3-A SYNCHRONOUS STEP-DOWN SWIFT™ CONVERTER WITH DISABLED SINKING DURING START-UP

TPS54377
www.ti.com
SLVS779 – SEPTEMBER 2007
1.6 MHz, 3-V TO 6-V INPUT, 3-A SYNCHRONOUS STEP-DOWN SWIFT™ CONVERTER
WITH DISABLED SINKING DURING START-UP
FEATURES
1
•2 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
• Disabled Current Sinking During Start-Up
• 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
DESCRIPTION
As a member of the SWIFT™ family of dc/dc
regulators, the TPS54377 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.
For reliable power up in output precharge
applications, the TPS54377 is designed to only
source current during start-up.
The TPS54377 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.
Simplified Schematic
*
*
START-UP WAVEFORM
Input
TPS54377
VIN
PH
PWRGD
SS/ENA BOOT
SYNC
PGND
RT
VBIAS ^VSENSE
AGND COMP
Output
R_L = 1 Ω
V_I = 3.3 V
V_O = 1.8 V
* Optional
5.0 ms/div
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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.
SWIFT, PowerPAD are trademarks of Texas Instruments.
2
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 © 2007, Texas Instruments Incorporated