- 1 -

www.active-semi.com

Copyright © 2008 Active-Semi, Inc.

TYPICAL APPLICATION CIRCUIT

ACT4082A

Rev0, 16-May-08

16V, 1.2A, 1.4MHz Step-Down DC/DC Converter in SOT23-6

FEATURES

APPLICATIONS

GENERAL DESCRIPTION

The ACT4082A is a current-mode step-down

DC/DC converter that supplies up to 1.2A into 5V

from a 12V input. 1.4MHz switching frequency al-

lows the use of tiny external components, and inter-

nal loop compensation provides simple, stable

power supplies with a minimum of external compo-

nents. Optimized for use with ceramic input and

output capacitors, the ACT4082A provides a very

compact 1.2A power supply for space constrained

mobile and consumer applications.

The ACT4082A operates over a wide input voltage

range and utilizes current-mode operation to pro-

vide excellent line and load transient response

while requiring no external compensation compo-

nents. Fault protection includes cycle-by-cycle cur-

rent limiting, frequency fold-back, hiccup mode, and

thermal shutdown. Internal soft-start provides a

controlled startup with no overshoot, even at light

loads.

The ACT4082A is available in a tiny SOT23-6 pack-

age and requires very few external components.

ACT4082A

IN

EN

BST

SW

FB

G

4.5V to 16V

OFF

ON

Active-Semi

Active-Semi