MP4350

2.5A, 4MHz, 20V

Step-Down Converter

MP4350 Rev. 1.0

www.MonolithicPower.com

1

5/26/2008

MPS Proprietary Information. Unauthorized Photocopy and Duplication Prohibited.

© 2008 MPS. All Rights Reserved.

The Future of Analog IC Technology

DESCRIPTION

The MP4350 is a high frequency step-down

switching regulator with an integrated internal

high-side high voltage power MOSFET. It

provides 2.5A output with current mode control

for fast loop response and easy compensation.

The

wide

4.5V

to

20V

input

range

accommodates

a

variety

of

step-down

applications, including those in an automotive

input

environment.

A

100µA

operational

quiescent current allows use in battery-powered

applications.

High power conversion efficiency over a wide

load range is achieved by scaling down the

switching frequency at light load condition to

reduce the switching and gate driving losses.

The frequency foldback helps prevent inductor

current runaway during startup and thermal

shutdown

provides

reliable,

fault

tolerant

operation.

By switching at 4MHz, the MP4350 is able to

prevent switching related EMI (Electromagnetic

Interference) noise problems, such as those

found in AM radio and ADSL applications.

The MP4350 is available in a small 3mm x 3mm

10-pin QFN package.

FEATURES

• 100µA Quiescent Current

• Wide 4.5V to 20V Operating Input Range

• 150mΩ Internal Power MOSFET

• Up to 4MHz Programmable Switching

Frequency

• Ceramic Capacitor Stable

• Internal Soft-Start

• Internal Set Current Limit without a Current

Sensing Resistor

• Up to 95% Efficiency

• Output Adjustable from 0.8V to 16V

• Available in a 10-Pin QFN (3mm x 3mm) Package

APPLICATIONS

• DSL Power

• Set Top Boxes

• Battery Powered Systems

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

Monolithic Power Systems, Inc.

TYPICAL APPLICATION

C3

220pF

C6

NS

C4

100nF

D1

3.3V

VIN

EN

FREQ

GND

BST

5

10

1,2

5

4

8,9

3

7

SW

FB

COMP

MP4350

EN

Efficiency vs

Load Current

100

90

80

70

60

50

40

30

0

0.5

1.0

1.5

2.0

2.5

LOAD CURRENT (A)