MP28253

21V, 3A, 500kHz

Synchronous Step-down Converter

MP28253 Rev. 1.02

www.MonolithicPower.com

1

12/25/2013

MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.

© 2013 MPS. All Rights Reserved.

The Future of Analog IC Technology

DESCRIPTION

The MP28253 is a high frequency synchronous

rectified step-down switch mode converter with

built in internal power MOSFETs. It offers a

very compact solution to achieve 3A continuous

output current over a wide input supply range

with excellent load and line regulation. The

MP28253 operates at high efficiency over a

wide output current load range.

Current mode operation provides fast transient

response and eases loop stabilization.

Full protection features include OCP and thermal

shut down.

The MP28253 requires a minimum number of

readily available standard external components

and is available in a space saving 3mm x 4mm

14-pin QFN package.

FEATURES

• Wide 4.5V to 21V Operating Input Range

• 3A Output Current

• Proprietary

Switching

Loss

Reduction

Technique

• Fixed 500kHz Switching Frequency

• External Soft-Start

• Sync from 300kHz to 2MHz External Clock

• Internal Compensation

• Integrated Bootstrap Diode

• Over-Current Protection and Hiccup

• Thermal Shutdown

• Output Adjustable from 0.8V

• Available in 14-pin QFN3x4 Package

APPLICATIONS

•

Notebook Systems and I/O Power

•

Networking Systems

•

Digital Set Top Boxes

•

Personal Video Recorders

•

Flat Panel Television and Monitors

•

Distributed Power Systems

All MPS parts are lead-free and adhere to the RoHS directive. For MPS green

status, please visit MPS website under Products, Quality Assurance page.

“MPS” and “The Future of Analog IC Technology” are registered trademarks of

Monolithic Power Systems, Inc.

The information in this datasheet about the product and its associated

technologies are proprietary and intellectual property of Monolithic Power

Systems and are protected by copyright and pending patent applications

TYPICAL APPLICATION （FOR NOTEBOOK）

C1

C5

47nF

MP28253

SW

SS

GND AGND

FB

EN/SYNC

IN

BST

VCC

PG

PG

R2

10k

Rt

24k

VOUT 1.2V/3A

R1

4.99k

R3

100k

VIN

ON/OFF

8

10

6

2,3,4,5

1

11

9

7

12,13

4.5V-21V

14