AT1312A/B/C

Preliminary Product Information

High Efficiency, Constant Current

White-LEDs Driver

7F, No.9,PARK AVENUE. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C.

Tel: 886-3-563-0878

Fax: 886-3-563-0879

2/23/2006 REV:1.1

1

Feature

•Operating Voltage:2.5V to 6.0V.

•High Operating Frequency: 1MHz

•High Output Voltage: Up to 16V/23V/28V

•Shutdown Current <1

µA

•16V/23V/28V Output Over-Voltage Protection

•Digital Dimming Control.

•Built-in Cycle-by Cycle Current-Limiting.

•Built-in Soft-Start Function.

•0.2V Low Reference Voltage

•Tiny SOT-26 Package

Application

• LED Module

• Compact Back Light Module

• Constant Current Source

Description

The AT1312A/B/C step-up converter drives white

LEDs with a constant current to provide backlight in

cell phones, PDAs, and other hand-held devices. It

features allowing series connection of the white

LEDs so that the LED currents are identical for

uniform brightness. An enable input can be pulsed

repeatedly to adjust LED’s brightness. The fast 1.0

MHz current-mode PWM control allows for smaller

capacitor and inductor. Fault condition protection

uses cycle-by-cycle current limiting to sense

maximum inductor current, thermal protection and

over-voltage protection. Also included soft-start

eliminates inrush current during start-up. The 0.2V

low reference voltage minimized the power loss

across the current-setting resistor.

The AT1312A/B/C is available in 6-pin SOT-26

packages.

Block Diagram

Aimtron reserves the right without notice to change this circuitry and specifications.