LM22671MRE-50 Datasheet, PDF (1/25 Pages) Texas Instruments – LM22671/LM22671-Q1 42V, 500mA SIMPLE SWITCHER® Step-Down Voltage Regulator

LM22671
www.ti.com
SNVS589M – SEPTEMBER 2008 – REVISED APRIL 2013
LM22671/LM22671-Q1 42V, 500mA SIMPLE SWITCHER® Step-Down Voltage Regulator
with Features
Check for Samples: LM22671
FEATURES
1
•2 Wide Input Voltage Range: 4.5V to 42V
• Internally Compensated Voltage Mode Control
• Stable with Low ESR Ceramic capacitors
• 200 mΩ N-Channel MOSFET
• Output Voltage Options:
– ADJ (Outputs as Low as 1.285V)
– 5.0 (Output Fixed to 5V)
• ±1.5% Feedback Reference Accuracy
• 500 kHz Default Switching Frequency
• Adjustable Switching Frequency and
Synchronization
• –40°C to 125°C Operating Junction
Temperature Range
• Precision Enable Pin
• Integrated Boot-Strap Diode
• Adjustable Soft-Start
• Fully WEBENCH^® Enabled
• LM22671-Q1 is an Automotive Grade Product
that is AEC-Q100 Grade 1 Qualified (-40°C to
+125°C Operating Junction Temperature)
PACKAGE
• SO PowerPAD (Exposed Pad)
APPLICATIONS
• Industrial Control
• Telecom and Datacom Systems
• Embedded Systems
• Conversions from Standard 24V, 12V and 5V
Input Rails
DESCRIPTION
The LM22671 switching regulator provides all of the
functions necessary to implement an efficient high
voltage step-down (buck) regulator using a minimum
of external components. This easy to use regulator
incorporates a 42V N-channel MOSFET switch
capable of providing up to 500mA of load current.
Excellent line and load regulation along with high
efficiency (>90%) are featured. Voltage mode control
offers short minimum on-time, allowing the widest
ratio between input and output voltages. Internal loop
compensation means that the user is free from the
tedious task of calculating the loop compensation
components. Fixed 5V output and adjustable output
voltage options are available. The default switching
frequency is set at 500 kHz allowing for small
external components and good transient response. In
addition, the frequency can be adjusted over a range
of 200 kHz to 1MHz with a single external resistor.
The internal oscillator can be synchronized to a
system clock or to the oscillator of another regulator.
A precision enable input allows simplification of
regulator control and system power sequencing. In
shutdown mode the regulator draws only 25 µA (typ.).
An adjustable soft-start feature is provided through
the selection of a single external capacitor. The
LM22671 also has built in thermal shutdown, and
current limiting to protect against accidental
overloads.
The LM22671 is a member of Texas Instruments'
SIMPLE SWITCHER™ family. The SIMPLE
SWITCHER™ concept provides for an easy to use
complete design using a minimum number of external
components and the TI WEBENCH^® design tool. TI's
WEBENCH^® tool includes features such as external
component calculation, electrical simulation, thermal
simulation, and Build-It boards for easy design-in.
1
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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.
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