TPS56428 Datasheet, PDF (1/22 Pages) Texas Instruments – 4.5V to 18 V Input, 4-A Synchronous Step-Down Converter with Advanced Eco-mode™

TPS56428
www.ti.com
SLVSBV4A – APRIL 2013 – REVISED APRIL 2013
4.5V to 18 V Input, 4-A Synchronous Step-Down Converter with Advanced Eco-mode™
Check for Samples: TPS56428
FEATURES
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•23 D-CAP2™ Mode Enables Fast Transient
Response
• Low Output Ripple and Allows Ceramic Output
Capacitor
• Wide V_IN Input Voltage Range: 4.5 V to 18 V
• Output Voltage Range: 0.6 V to 7.0 V
• Highly Efficient Integrated FETs Optimized
for Lower Duty Cycle Applications
– 68 mΩ (High Side) and 37 mΩ (Low Side)
• High Efficiency, Less Than 10 μA at Shutdown
• High Initial Bandgap Reference Accuracy
• Pre-Biased Soft Start
• 650-kHz Switching Frequency (f_SW)
• Cycle By Cycle Over Current Limit
• Advanced Auto-Skip Eco-mode™ for High
Efficiency at Light Load
• Power Good output
• Fixed Soft Start : 1.0ms
APPLICATIONS
• Wide Range of Applications for Low Voltage
System
– Digital TV Power Supply
– High Definition Blu-ray Disc™ Players
– Networking Home Terminal
– Digital Set Top Box (STB)
DESCRIPTION
The TPS56428 is an adaptive on-time D-CAP2™
mode synchronous buck converter.
The TPS56428 enables system designers to
complete the suite of various end-equipment power
bus regulators with a cost effective, low component
count, low standby current solution.
The main control loop for the TPS56428 uses the D-
CAP2™ mode control that provides a fast transient
response with no external compensation
components.
The adaptive on-time control supports seamless
transition between PWM mode at higher load
conditions and advanced Eco-mode™ operation at
light loads.
Advanced Eco-mode™ allows the TPS56428 to
maintain high efficiency during lighter load conditions.
The TPS56428 also has a proprietary circuit that
enables the device to adopt to both low equivalent
series resistance (ESR) output capacitors, such as
POSCAP or SP-CAP, and ultra-low ESR ceramic
capacitors. The device operates from 4.5-V to 18 V
VIN input.
The output voltage can be programmed between
0.6V and 7.0V.
The device also features a fixed 1 msec soft start
time.
The TPS56428 is available in 8-pin DDA package
and is designed to operate over the ambient
temperature range of –40°C to 85°C.
TPS56428
Vout( 50mV/div)
Iout( 2A/div)
100us/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.
D-CAP2, Eco-mode are trademarks of Texas Instruments.
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Blu-ray Disc is a trademark of Blu-ray Disc Association.
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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