Voltage

5V/5A

2 x 180 PF/16V

22 PH

L

Feedback

Boost

6TQ045S

Ground

Current

Softstart

1 nF

+

Voltage

8V to 40V

Input

LM2679 - 5.0

Output

Switch

Output

0.01 PF

+

Limit

Adjust

5.6k

0.47 PF

+

+

+

3 x 15 PF/50V

=

37,125

I

CL

LM2679

www.ti.com

SNVS026N – MARCH 2000 – REVISED APRIL 2013

Limit

Check for Samples: LM2679

1

FEATURES

DESCRIPTION

The LM2679 series of regulators are monolithic

2

•

Efficiency Up to 92%

integrated circuits which provide all of the active

•

Simple and Easy to Design with (Using Off-

functions for a step-down (buck) switching regulator

The-Shelf External Components)

capable of driving up to 5A loads with excellent line

•

Resistor Programmable Peak Current Limit

and load regulation characteristics. High efficiency

(>90%) is obtained through the use of a low ON-

Over a Range of 3A to 7A.

resistance DMOS power switch. The series consists

•

120 m

Ω DMOS Output Switch

of fixed output voltages of 3.3V, 5V and 12V and an

•

3.3V, 5V and 12V Fixed Output and Adjustable

adjustable output version.

(1.2V to 37V ) Versions

•

±2% Maximum Output Tolerance Over Full

complete design using a minimum number of external

Line and Load Conditions

components.

A

high

fixed

frequency

oscillator

•

Wide Input Voltage Range: 8V to 40V

(260KHz) allows the use of physically smaller sized

components. A family of standard inductors for use

•

260 KHz Fixed Frequency Internal Oscillator

with

the

LM2679

are

available

from

several

•

Softstart Capability

manufacturers to greatly simplify the design process.

•

−40 to +125°C Operating Junction Temperature

Other features include the ability to reduce the input

Range

surge current at power-ON by adding a softstart

timing capacitor to gradually turn on the regulator.

APPLICATIONS

The

LM2679

series

also

has

built

in

thermal

shutdown and resistor programmable current limit of

•

Simple to Design, High Efficiency (>90%) Step-

the power MOSFET switch to protect the device and

Down Switching Regulators

load circuitry under fault conditions. The output

•

Efficient System Pre-Regulator for Linear

voltage is specified to a ±2% tolerance. The clock

Voltage Regulators

frequency is controlled to within a ±11% tolerance.

•

Battery Chargers

Typical Application

1

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.

2

SIMPLE SWITCHER, Switchers Made Simple are registered trademarks of Texas Instruments.

PRODUCTION DATA information is current as of publication date.

Copyright © 2000–2013, Texas Instruments Incorporated

Products conform to specifications per the terms of the Texas

Instruments standard warranty. Production processing does not

necessarily include testing of all parameters.