LM27341_14 Datasheet, PDF (1/42 Pages) Texas Instruments – 2 MHz 1.5A/2A Wide Input Range Step-Down DC-DC Regulator with Frequency Synchronization

LM27341, LM27342, LM27341Q, LM27342Q
www.ti.com
SNVS497D – NOVEMBER 2008 – REVISED FEBRUARY 2010
LM27341/LM27342/LM27341Q/LM27342Q 2 MHz 1.5A/2A Wide Input Range Step-Down DC-
DC Regulator with Frequency Synchronization
Check for Samples: LM27341, LM27342, LM27341Q, LM27342Q
FEATURES
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•2 Space Saving 3 x 3 mm 10-Pin SON and
MSOP-PowerPad Packages
• Wide Input Voltage Range: 3V to 20V
• Wide Output Voltage Range: 1V to 18V
• LM27341 Delivers 1.5A Maximum Output
Current
• LM27342 Delivers 2A Maximum Output Current
• High Switching Frequency: 2 MHz
• Frequency Synchronization: 1.00 MHz < f_SW <
2.35 MHz
• 150 mΩ NMOS Switch with Internal Bootstrap
Supply
• 70 nA Shutdown Current
• Internal Voltage Reference Accuracy of 1%
• Peak Current-Mode, PWM Operation
• Thermal Shutdown
• LM27341Q and LM27342Q are AEC-Q100
Grade 1 Qualified and are Manufactured on an
Automotive Grade Flow
APPLICATIONS
• Local 12V to Vcore Step-Down Converters
• Radio Power Supply
• Core Power in HDDs
• Set-Top Boxes
• Automotive
• USB Powered Devices
• DSL Modems
DESCRIPTION
The LM27341 and LM27342 regulators are
monolithic, high frequency, PWM step-down DC-DC
converters in 10-pin SON and 10-pin MSOP-
PowerPad packages. They contain all the active
functions to provide local DC-DC conversion with fast
transient response and accurate regulation in the
smallest possible PCB area.
With a minimum of external components the
LM27341 and LM27342 are easy to use. The ability
to drive 1.5A or 2A loads respectively, with an internal
150 mΩ NMOS switch results in the best power
density available. The world-class control circuitry
allows for on-times as low as 65 ns, thus supporting
exceptionally high frequency conversion. Switching
frequency is internally set to 2 MHz and
synchronizable from 1 to 2.35 MHz, which allows the
use of extremely small surface mount inductors and
chip capacitors. Even though the operating frequency
is very high, efficiencies up to 90% are easy to
achieve. External shutdown is included featuring an
ultra-low shutdown current of 70 nA. The LM27341
and LM27342 utilize peak current-mode control and
internal compensation to provide high-performance
regulation over a wide range of operating conditions.
Additional features include internal soft-start circuitry
to reduce inrush current, pulse-by-pulse current limit,
thermal shutdown, and output over-voltage
protection.
1
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Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
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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 © 2008–2010, Texas Instruments Incorporated