LM2734_15 Datasheet, PDF (1/37 Pages) Texas Instruments – LM2734 Thin SOT 1-A Load Step-Down DC-DC Regulator

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LM2734
SNVS288J – SEPTEMBER 2004 – REVISED DECEMBER 2014
LM2734 Thin SOT 1-A Load Step-Down DC-DC Regulator
1 Features
•1 Thin SOT-6 Package
• 3.0-V to 20-V Input Voltage Range
• 0.8-V to 18-V Output Voltage Range
• 1-A Output Current
• 550-kHz (LM2734Y) and 1.6-MHz (LM2734X)
Switching Frequencies
• 300-mΩ NMOS Switch
• 30-nA Shutdown Current
• 0.8-V, 2% Internal Voltage Reference
• Internal Soft-Start
• Current-Mode, PWM Operation
• WEBENCH^® Online Design Tool
• Thermal Shutdown
• LM2734XQ and LM2734YQ are AEC-Q100 Grade
1 Qualified and are Manufactured on an
Automotive Grade Flow.
2 Applications
• Local Point-of-Load Regulation
• Core Power in HDDs
• Set-Top Boxes
• Battery-Powered Devices
• USB Powered Devices
• DSL Modems
• Notebook Computers
• Automotive
Typical Application Circuit
D2
3 Description
The LM2734 regulator is a monolithic, high-
frequency, PWM step-down DC-DC converter in a 6-
pin Thin SOT package. The device 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 LM2734
regulator is easy to use. The ability to drive 1-A loads
with an internal 300-mΩ NMOS switch using state-of-
the-art 0.5-µm BiCMOS technology results in the best
power density available. The world-class control
circuitry allows for on-times as low as 13 ns, thus
supporting exceptionally high-frequency conversion
over the entire 3-V to 20-V input operating range
down to the minimum output voltage of 0.8 V.
Switching frequency is internally set to 550 kHz
(LM2734Y) or 1.6 MHz (LM2734X), allowing the use
of extremely small surface-mount inductors and chip
capacitors. Even though the operating frequencies
are very high, efficiencies up to 90% are easy to
achieve. External shutdown is included, featuring an
ultra-low standby current of 30 nA.
The LM2734 regulator uses 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 overvoltage protection.
Device Information⁽¹⁾
PART NUMBER
PACKAGE
BODY SIZE (NOM)
LM2734
SOT (6)
2.90 mm x 1.60 mm
(1) For all available packages, see the orderable addendum at
the end of the datasheet.
Efficiency vs Load Current
V_IN = 5 V, V_OUT = 3.3 V
VIN
C1
ON
OFF
VIN
BOOST
C3
SW
LM2734
D1
EN
FB
GND
L1
VOUT
C2
R1
R2
1
An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications,
intellectual property matters and other important disclaimers. PRODUCTION DATA.