GND

FB

EN

SW

C1

R3

D1

L1

R2

R1

C2

C3

LM2831

LM2831

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SNVS422B – AUGUST 2006 – REVISED JANUARY 2012

LM2831 High Frequency 1.5A Load - Step-Down DC-DC Regulator

Check for Samples: LM2831

1

FEATURES

DESCRIPTION

The LM2831 regulator is a monolithic, high frequency,

2

•

Space Saving SOT-23 Package

PWM step-down DC/DC converter in a 5 pin SOT-23

•

Input Voltage Range of 3.0V to 5.5V

and a 6 Pin WSON package. It provides all the active

•

Output Voltage Range of 0.6V to 4.5V

functions to provide local DC/DC conversion with fast

transient response and accurate regulation in the

•

1.5A Output Current

smallest possible PCB area. With a minimum of

•

High Switching Frequencies

external components, the LM2831 is easy to use. The

–

1.6MHz (LM2831X)

ability to drive 1.5A loads with an internal 130 m

Ω

PMOS switch using state-of-the-art 0.5 µm BiCMOS

–

0.55MHz (LM2831Y)

technology

results

in

the

best

power

density

–

3.0MHz (LM2831Z)

available. The world-class control circuitry allows on-

•

130m

Ω PMOS Switch

times as low as 30ns, thus supporting exceptionally

high frequency conversion over the entire 3V to 5.5V

•

0.6V, 2% Internal Voltage Reference

input operating range down to the minimum output

•

Internal Soft-Start

voltage of 0.6V. Switching frequency is internally set

•

Current Mode, PWM Operation

to 550 kHz, 1.6 MHz, or 3.0 MHz, allowing the use of

•

Thermal Shutdown

extremely small surface mount inductors and chip

capacitors. Even though the operating frequency is

•

Over Voltage Protection

high, efficiencies up to 93% are easy to achieve.

External shutdown is included, featuring an ultra-low

APPLICATIONS

stand-by current of 30 nA. The LM2831 utilizes

•

Local 5V to Vcore Step-Down Converters

current-mode control and internal compensation to

provide high-performance regulation over a wide

•

Core Power in HDDs

range of operating conditions. Additional features

•

Set-Top Boxes

include internal soft-start circuitry to reduce inrush

•

USB Powered Devices

current,

pulse-by-pulse

current

limit,

thermal

shutdown, and output over-voltage protection.

•

DSL Modems

Typical Application Circuit

1

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Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.

2

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PRODUCTION DATA information is current as of publication date.

Copyright © 2006–2012, 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.