LM2734Z_14 Datasheet, PDF (1/29 Pages) Texas Instruments – Thin SOT23 1A Load Step-Down DC-DC Regulator

LM2734Z
www.ti.com
SNVS334D – JANUARY 2005 – REVISED JUNE 2008
LM2734Z/LM2734ZQ Thin SOT23 1A Load Step-Down DC-DC Regulator
Check for Samples: LM2734Z
FEATURES
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•23 Thin SOT23-6 package, or 6 lead LLP package
• 3.0V to 20V input voltage range
• 0.8V to 18V output voltage range
• 1A output current
• 3MHz switching frequency
• 300mΩ NMOS switch
• 30nA shutdown current
• 0.8V, 2% internal voltage reference
• Internal soft-start
• Current-Mode, PWM operation
• Thermal shutdown
• LM2734ZQ is AEC-Q100 Grade 1 qualified and
is manufactured on an Automotive Grade Flow
APPLICATIONS
• DSL Modems
• Local Point of Load Regulation
• Battery Powered Devices
• USB Powered Devices
• Automotive
DESCRIPTION
The LM2734Z regulator is a monolithic, high frequency, PWM step-down DC/DC converter assembled in a 6-pin
Thin SOT23 and LLP non pull back package. It provides 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 and online design support through WEBENCH®™, the LM2734Z is
easy to use. The ability to drive 1A loads with an internal 300mΩ NMOS switch using state-of-the-art 0.5µm
BiCMOS technology results in the best power density available. The world class control circuitry allows for on-
times as low as 13ns, thus supporting exceptionally high frequency conversion over the entire 3V to 20V input
operating range down to the minimum output voltage of 0.8V. Switching frequency is internally set to 3MHz,
allowing the use of extremely small surface mount inductors and chip capacitors. Even though the operating
frequency is very high, efficiencies up to 85% are easy to achieve. External shutdown is included, featuring an
ultra-low stand-by current of 30nA. The LM2734Z utilizes 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.
TYPICAL APPLICATION CIRCUIT
V_IN
C1
ON
OFF
D2
V_IN
BOOST
C3
SW
LM2734
D1
EN
FB
GND
L1
V_OUT
C2
R1
R2
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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.
WEBENCH® is a trademark of Texas Instruments, Inc..
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All other trademarks are the property of their respective owners.
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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 © 2005–2008, Texas Instruments Incorporated