© Semiconductor Components Industries, LLC, 2010

September, 2010 − Rev. 5

1

Publication Order Number:

NCP1529/D

NCP1529

1.7MHz, 1A, High Efficiency,

Low Ripple, Adjustable

Output Voltage Step-down

Converter

The NCP1529 step−down DC−DC converter is a monolithic

integrated circuit for portable applications powered from one cell

Li−ion or three cell Alkaline/NiCd/NiMH batteries. The device is able

to deliver up to 1.0 A on an output voltage range externally adjustable

from 0.9 V to 3.9 V or fixed at 1.2 V or 1.35 V. It uses synchronous

rectification to increase efficiency and reduce external part count. The

device also has a built−in 1.7 MHz (nominal) oscillator which reduces

component size by allowing a small inductor and capacitors. Automatic

switching PWM/PFM mode offers improved system efficiency.

Additional features include integrated soft−start, cycle−by−cycle

current limiting and thermal shutdown protection.

The NCP1529 is available in a space saving, low profile

2x2x0.5 mm UDFN6 package and TSOP−5 package.

Features

Typical Applications

GND

VIN

EN

SW

FB

OFF ON

R1

R2

Figure 1. Typical Application for Adjustable Version

L

GND

VIN

EN

SW

FB

OFF ON

Figure 2. Typical Application for Fixed Version

L

TSOP−5

SN SUFFIX

CASE 483

http://onsemi.com

MARKING

DIAGRAM

1

5

DXJ

= Specific Device Code

A

= Assembly Location

Y

= Year

W

= Work Week

G

= Pb−Free Package

(Note: Microdot may be in either location)

1

5

DXJAYWG

G

XXMG

G

1

2

3

6

5

4

UDFN6

MU SUFFIX

CASE 517AB

XX

= Specific Device Code

M

= Date Code

G

= Pb−Free Package

(Note: Microdot may be in either location)

See detailed ordering and shipping information in the package

dimensions section on page 14 of this data sheet.

ORDERING INFORMATION