MP2128

2.5V-6V Input, 3MHz, 1A

Synchronous Step-Down Converter

MP2128 Rev. 0.9

www.MonolithicPower.com

1

7/20/2009

MPS Proprietary Information. Unauthorized Photocopy and Duplication Prohibited.

© 2009 MPS. All Rights Reserved.

The Future of Analog IC Technology

DESCRIPTION

The MP2128 is a 3MHz constant frequency,

current mode, PWM step-down converter with

integrated

main

switch

and

synchronous

rectifier that is ideal for powering portable

equipment that runs from a single Li-Ion or Li-

Polymer battery.

The MP2128 can supply up to 1A load current

from a 2.5V to 6V input voltage. The output

voltage can be as low as 0.6V.

Additional features include <1µA shutdown

current, internal soft-start, cycle-by-cycle over

current protection, short circuit protection, and

thermal shutdown.

The MP2128 is available in low profile (1.5mm)

5-pin SOT23 and 8-pin, QFN8 2mm×2mm

packages.

FEATURES

• High Efficiency: Up to 95%

• 3MHz Constant Switching Frequency

• 1A Available Load Current

• 2.5V to 6V Input Voltage Range

• Output Voltage as Low as 0.6V

• Current Mode Control

• Cycle-by-Cycle Over Current Protection

• Short Circuit Protection

• Thermal Shutdown

• <1µA Shutdown Current

• Internal Soft-Start

• Space Saving 5-Pin SOT23 Package and

• 8-pin, QFN8 2mm×2mm package

APPLICATIONS

• Cellular Phones

• Microprocessors and DSP Core Supplies

• PDAs and Smart Phones

• MP3 and Portable Media Players

• Digital Still and Video Cameras

• Portable Instruments

“MPS” and “The Future of Analog IC Technology” are Registered Trademarks of

Monolithic Power Systems, Inc.

TYPICAL APPLICATION

OFF ON

EN

IN

VIN

SW

SW

NC

FB

PGND

AGND

U1

VOUT

1.8V 1A

2.5V--6V

3

8

7

6

5

1

4

2

R1

200k

1%

R2

100k

1%

MP2128DG