AAT1274

1.5A Single Flash LED Driver IC

DATA SHEET

1

Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com

201981A • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • May 21, 2012

General Description

The AAT1274 is a high-efficiency, 1.5A high-current

boost converter for LED photo flash applications. It

maintains output current regulation by switching the

internal high-side and low-side switch transistors, pulse-

width modulated at a fixed frequency of 2MHz. The high

switching frequency allows the use of a small external

inductor and output capacitor, making the AAT1274 ide-

ally suited in all single cell, Li-ion-powered applications.

Serial Control™) serial digital interface is used to enable,

disable, configure, and program the operation of the

current level for each LED, and the flash-to-movie-mode

current ratio can be programmed to one of 16 levels. The

AAT1274 includes a separate Flash Enable input to initi-

ate the flash operation and a Flash Inhibit pin which

reduces the flash current to movie-mode levels during

high battery demand.

The maximum flash and movie-mode current is set by

one external resistor where the ratio of flash to movie-

mode current is set at approximately 7.3:1. The AAT1274

can drive one high current LED.

The AAT1274 contains a thermal management system to

protect the device in the event of an output short-circuit

condition. Built-in circuitry prevents excessive inrush

current during start-up. The shutdown feature reduces

quiescent current to less than 1.0μA.

The AAT1274 is available in a Pb-free, thermally-enhanced

TDFN33-14 package and operates over the -40°C to 85°C

temperature range.

Features

• Input Voltage Range: 2.7V to 5.5V

• Single Channel Flash Output

• Up to 1.5A Regulated Output Current

• Up to 88% Efficiency

• 2 MHz Switching Frequency

• Separate Flash Enable

• Single Resistor Sets Flash and Movie Mode Current

• Movie Mode Current

• Flash/Movie Mode Current Ratio

• True Load Disconnect

• Soft-Start and Input Current Limit

• Over-Voltage (Open LED, Open Circuit), Short Circuit,

and Over-Temperature Protection

• -40°C to +85°C Temperature Range

• TDFN33-14 Package

Applications

• LED Photo Flash / Torch

• Camera Enabled Mobile Devices

• Cellphones/Smartphones

• Digital Still Cameras (DSCs)

• Multimedia Mobile Phones

Typical Application

AAT1274

R

SET

C

IN

2.2μF

C

OUT

2.2μF

IN

OUT

EN/SET

FLEN

AGND

PGND

FLGND

RSET

Flash LED

Enable/Set Input

Flash Enable

FL

V

SW

L1 1μH

FLINH

Flash Inhibit