MP1423

3A, 23V, 385KHz

Step-Down Converter

MP1423 Rev. 1.1

www.MonolithicPower.com

1

1/6/2006

MPS Proprietary Information. Unauthorized Photocopy and Duplication Prohibited.

© 2006 MPS. All Rights Reserved.

The Future of Analog IC Technology

TM

TM

DESCRIPTION

The MP1423 is a step-down regulator with a

built in internal Power MOSFET. It achieves 3A

continuous output current over a wide input

supply range with excellent load and line

regulation.

Current mode operation provides fast transient

response and eases loop stabilization.

Fault condition protection includes cycle-by-cycle

current

limiting

and

thermal

shutdown.

Adjustable soft-start reduces the stress on the

input source at turn-on. In shutdown mode the

regulator draws 20µA of supply current.

The MP1423 requires a minimum number of

readily

available

external

components

to

complete a 3A step-down DC to DC converter

solution.

FEATURES

• 3A Output Current

• Programmable Soft-Start

• 110mΩ Internal Power MOSFET Switch

• Stable with Low ESR Output Ceramic Capacitors

• Up to 94% Efficiency

• 20µA Shutdown Mode

• Fixed 385KHz Frequency

• Thermal Shutdown

• Cycle-by-Cycle Over Current Protection

• Wide 6V to 23V Operating Input Range

• Output is Adjustable From 1.22V to 21V

• Under Voltage Lockout

APPLICATIONS

• Distributed Power Systems

• Battery Chargers

• Pre-Regulator for Linear Regulators

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

Power Systems, Inc.

TYPICAL APPLICATION

INPUT

6V to 23V

OUTPUT

2.5V

3A

MP1423

BS

IN

FB

SW

SS

GND

COMP

EN

OPEN

OPEN =

AUTOMATIC

STARTUP

MP1423_TAC01

10nF

5.6nF

10nF

B330A

1

3

5

6

4

8

7

2

MP1423_EC01

Efficiency vs Load Current

100

90

80

70

60

50

0

0.5 1.0 1.5 2.0 2.5 3.0 3.5

LOAD CURRENT (A)

VOUT=5.0V

VIN = 10V

VOUT=2.5V

VOUT=3.3V