LM2675EP

High Efficiency 1A Step-Down Voltage Regulator

General Description

The LM2675EP 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) and a fixed frequency oscillator.

The LM2675EP 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-

per traces on the printed circuit board are the only heat

sinking needed.

A family of standard inductors for use with the LM2675EP

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.

output voltage within specified input voltages and output

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 LM2675EP 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

1.5% max output voltage tolerance over line and load

conditions

n

Guaranteed 1A output load current

n

0.25

Ω 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

Thermal shutdown and current limit protection

Typical Applications

n

Regulator

n

Efficient Pre-Regulator for Linear Regulators

n

Positive-to-Negative Converter

n

Selected Military Applications

n

Selected Avionics Applications

Ordering Information

PART NUMBER

VID PART NUMBER

NS PACKAGE NUMBER (Note 3)

LM2675MX-ADJEP

V62/04630-01

M08A

(Notes 1, 2)

TBD

TBD

Note 1: For

the

following

(Enhanced

Plastic)

versions,

check

for

availability:

LM2675LD-12EP,

LM2675LDX-12EP,

LM2675LD-3.3EP, LM2675LDX-3.3EP, LM2675LD-5.0EP, LM2675LDX-5.0EP, LM2675LD-ADJEP, LM2675LDX-ADJEP, LM2675M-12EP, LM2675MX-12EP,

LM2675M-3.3EP,

LM2675MX-3.3EP,

LM2675M-5.0EP,

LM2675MX-5.0EP,

LM2675M-ADJEP,

LM2675N-12EP,

LM2675N-3.3EP,

LM2675N-5.0EP,

LM2675N-ADJEP. Parts listed with an "X" are provided in Tape & Reel and parts without an "X" are in Rails.

Note 2: FOR ADDITIONAL ORDERING AND PRODUCT INFORMATION, PLEASE VISIT THE ENHANCED PLASTIC WEB SITE AT: www.national.com/

mil

Note 3: Refer to package details under Physical Dimensions

May 2004

© 2004 National Semiconductor Corporation

DS200994

www.national.com