TPS54326_16 Datasheet, PDF (1/30 Pages) Texas Instruments – 4.5V to 18V Input, 3-A Synchronous Step-Down Converter with Eco-mode

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TPS54326
SLVSA13E – OCTOBER 2009 – REVISED JUNE 2012
4.5V to 18V Input, 3-A Synchronous Step-Down Converter with Eco-mode™
Check for Samples: TPS54326
FEATURES
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•23 D-CAP2™ Mode Enables Fast Transient
Response
• Low Output Ripple and Allows Ceramic Output
Capacitor
• Wide V_CC Input Voltage Range: 4.5 V to 18 V
• Wide V_IN Input Voltage Range: 2 V to 18 V
• Output Voltage Range: 0.76 V to 5.5 V
• Highly Efficient Integrated FET’s Optimized
for Lower Duty Cycle Applications
- 120 mΩ (High Side) and 70 mΩ (Low Side)
• High Efficiency, less than 10 μA at Shutdown
• Auto-Skip Eco-mode™ for High Efficiency at
Light Load
• High Initial Bandgap Reference Accuracy
• Adjustable Soft Start
• Pre-Biased Soft Start
• 700-kHz Switching Frequency (f_SW)
• Cycle-By-Cycle Overcurrent Limit
• Power Good Output
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 TPS54326 is an adaptive on-time D-CAP2™
mode synchronous buck converter. The TPS54326
enables system designers to complete the suite of
various end equipment’s power bus regulators with a
cost effective, low component count, low standby
current solution. The main control loop for the
TPS54326 uses the D-CAP2™ mode control which
provides a fast transient response with no external
components. The adoptive on-time control supports
seamless operation between PWM mode at heavy
load condition and reduced frequency Eco-mode™
operation at light load for high efficiency.
The TPS54326 also has a proprietary circuit that
enables the device to adapt 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
V_CC input , and from 2-V to 18-V VIN input power
supply voltage. The output voltage can be
programmed between 0.76 V and 5.5 V. The device
also features an adjustable slow start time and a
power good function. The TPS54326 is available in
the 14 pin HTSSOP or 16 pin QFN package, and
designed to operate from –40°C to 85°C.
V_OUT (50 mV/div)
I_OUT (1 A/div)
100 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.
D-CAP2, Eco-mode, PowerPAD 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 © 2009–2012, Texas Instruments Incorporated