FEATURES

2• Accurate and Programmable LED Current up

to 1.2A in 128 Steps

• Total Solution Size < 30mm2

• 90% Peak Efficiency

• Drives 2 LEDs in Series with 1.2A from 5V

Input

• Drives 2 LEDs in Series with 600mA from 3.0V

Input

• Drives 1 LED with 1.2A from 3.0V Input

• Adjustable Over-Voltage Protection Allows for

Single or Series LED Operation

• Four Operating Modes: Torch, Flash, Indicator,

and Voltage Mode (4.98V)

• Programmable Flash Pulse Safety Timer in 16

Steps

• TX Input Ensures Synchronization with RF

Power Amplifier Pulse or Prevents LED from

Overheating

• LED Disconnect During Shutdown

• Flash/Imager Synchronization via F EN Pin

• Active Low Hardware Reset

• Multi-Function Pin (RESET and GPIO)

• Low Profile 12-pin WSON Package

(DQB0012A: 3mm x 3mm x 0.8mm, 0.4mm

pitch)

APPLICATIONS

• Camera Phone LED Flash

• Smartphone and PDA Flash

• LED Backlight

DESCRIPTION

The LM3553 is a fixed frequency, current mode step- up DC/DC converter with two regulated current sinks.

The device is capable of driving loads up to 1.2A

from a single-cell Li-Ion battery.

The LM3553 includes a TX pin that forces Torch

mode during a flash event allowing for

synchronization between the RF power amplifier and

Flash/Torch modes. It also includes a multi-function

pin (M/F) that can serve as a GPIO and a hardware

RESET pin.

The LM3553 is available in a 3mm by 3mm package.