LM2672EP Datasheet, PDF (1/25 Pages) National Semiconductor (TI) – Enhanced Plastic SIMPLE SWITCHER Power Converter High Efficiency 1A Step-Down Voltage Regulator with Features

August 2004
LM2672EP
Enhanced Plastic SIMPLE SWITCHER^® Power Converter
High Efficiency 1A Step-Down Voltage Regulator with
Features
General Description
The LM2672EP series of regulators are monolithic inte-
grated circuits built with a LMDMOS process. These regula-
tors provide all the active functions for a step-down (buck)
switching regulator, capable of driving a 1A load current with
excellent line and load regulation. These devices are avail-
able in fixed output voltages of 3.3V, 5.0V, 12V, and an
adjustable output version.
Requiring a minimum number of external components, these
regulators are simple to use and include patented internal
frequency compensation (Patent Nos. 5,382,918 and
5,514,947), fixed frequency oscillator, external shutdown,
soft-start, and frequency synchronization.
The LM2672EP series operates at a switching frequency of
260 kHz, thus allowing smaller sized filter components than
what would be needed with lower frequency switching regu-
lators. Because of its very high efficiency (>90%), the cop-
per traces on the printed circuit board are the only heat
sinking needed.
A family of standard inductors for use with the LM2672EP
are available from several different manufacturers. This fea-
ture greatly simplifies the design of switch-mode power sup-
plies using these advanced ICs. Also included in the
datasheet are selector guides for diodes and capacitors
designed to work in switch-mode power supplies.
Other features include a guaranteed ±1.5% tolerance on
output voltage within specified input voltages and output
load conditions, and ±10% on the oscillator frequency. Ex-
ternal shutdown is included, featuring typically 50 µA
stand-by current. The output switch includes current limiting,
as well as thermal shutdown for full protection under fault
conditions.
To simplify the LM2672EP buck regulator design procedure,
there exists computer design software, LM267X Made
Simple version 6.0.
ENHANCED PLASTIC
• Extended Temperature Performance of −40˚C to +125˚C
• Baseline Control - Single Fab & Assembly Site
• Process Change Notification (PCN)
• Qualification & Reliability Data
• Solder (PbSn) Lead Finish is standard
• Enhanced Diminishing Manufacturing Sources (DMS)
Support
Features
n Efficiency up to 96%
n Available in SO-8, 8-pin DIP and LLP packages
n Computer Design Software LM267X Made Simple
version 6.0
n Simple and easy to design with
n Requires only 5 external components
n Uses readily available standard inductors
n 3.3V, 5.0V, 12V, and adjustable output versions
n Adjustable version output voltage range: 1.21V to 37V
n ±1.5% max output voltage tolerance over line and load
conditions
n Guaranteed 1A output load current
n 0.25Ω DMOS Output Switch
n Wide input voltage range: 8V to 40V
n 260 kHz fixed frequency internal oscillator
n TTL shutdown capability, low power standby mode
n Soft-start and frequency synchronization
n Thermal shutdown and current limit protection
Typical Applications
n Simple High Efficiency (>90%) Step-Down (Buck)
Regulator
n Efficient Pre-Regulator for Linear Regulators
n Selected Military Applications
n Selected Avionics Applications
Ordering Information
PART NUMBER
LM2672MX-ADJEP
(Notes 1, 2)
VID PART NUMBER
V62/04629-01
TBD
NS PACKAGE NUMBER (Note 3)
M08A
TBD
SIMPLE SWITCHER^® is a registered trademark of National Semiconductor Corporation.
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© 2004 National Semiconductor Corporation DS200978
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