LP3931

Dual RGB LED Driver with High Current Boost DC-DC

Converter

General Description

The LP3931 is a RGB LED driver with high current boost

DC-DC converter designed for portable wireless applica-

tions. It contains 2 sets of RGB LED drivers that are PWM-

driven with programmable color, intensity and blinking pat-

terns. They additionally feature a FLASH function to support

picture taking with camera-enabled cellular phones.

An efficient magnetic boost DC/DC converter provides the

required bias, operating from a single Li-Ion battery. The

DC/DC converter output voltage is user programmable for

adapting to different LED types and for efficiency optimiza-

tion.

All functions are software controllable through the SPI inter-

face and internal registers.

Features

n

High Efficiency Programmable 300 mA Magnetic Boost

DC-DC converter

n

2 separately controlled PWM RGB LED drivers with

programmable color, brightness, turn on/off slopes and

blinking patterns

n

FLASH function with up to 6 outputs, each up to

120 mA

n

Functions software controlled through SPI interface

n

Additional LED on/off and dimming hardware control

n

Programmable low current Standby mode

n

Low voltage digital interface down to 1.8V

n

Space efficient 24-pin LLP package

Applications

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GSM Cellular Phones

n

WCDMA, CDMA and CDMA2000 Phones

n

PHS and PDC Cellular Phone

Typical Application

20117301

August 2004

© 2004 National Semiconductor Corporation

DS201173

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