LP8543

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SNVS604D – AUGUST 2009 – REVISED MARCH 2013

SMBus/I2C Controlled WLED Driver for Medium-Sized LCD Backlight

Check for Samples: LP8543

1

FEATURES

DESCRIPTION

The LP8543 is a white LED driver with integrated

2

•

High-Voltage DC/DC Boost Converter with

boost converter. It has 7 adjustable current sinks

Integrated FET

•

5.5V to 22V Input Voltage Range to Support 2x,

serial interface, PWM input and Ambient Light Sensor

3x and 4x Li-Ion Batteries.

(ALS).

•

PWM Phase Shift Control with Adaptive Boost

The boost converter has adaptive output voltage

Output to Increase Efficiency Compared to

control based on the LED driver voltages. This

Conventional Boost Converters Topologies

feature

minimizes

the

power

consumption

by

•

PWM Brightness Control for Single Wire

adjusting the voltage to lowest sufficient level in all

conditions. Phase Shift PWM dimming offers further

Control and Stand-Alone Use

power saving especially when there is poor matching

•

Digital Ambient Light Sensor Interface with

in the forward voltages of the LED strings. Boost

User-Programmed Ambient Light to Backlight

voltage

can

also

be

controlled

through

the

Brightness Curve

•

Easy-to-Use EEPROM Calibration for Current,

Internal EEPROM stores the data for backlight

Intensity and Ambient Light Response Setting

brightness and ambient light sensor calibration.

•

Seven LED Drivers with LED Fault

Brightness can be calibrated during the backlight unit

(Short/open) Detection

production so that all units produce the same

brightness. EEPROM also stores the coefficients for

•

Eight-Bit LED Current Control

the LED control equations and the default LED

•

Internal Thermal Protection and Backlight

current value. LED current has 8–bit adjustment from

Safety Dimming Feature

0 to 60 mA.

•

The LP8543 has several safety and diagnostic

Interface

features. Low-input voltage detection turns the chip

•

Low-Input Voltage Detection and Shutdown

off if the system gets stuck and battery fully

discharges. Input voltage detection threshold is

•

Minimum Number of External Components

adjustable

for

different

battery

configurations.

•

WQFN 24-Pin Package, 4 x 4 x 0.8 mm

Thermal

regulation

reduces

backlight

brightness

above a set temperature. LED fault detection reports

APPLICATIONS

open or LED short fault. Boost over-current fault

•

Medium Sized (>10 inches) LCD Display

detection protects the chip in case of over-current

event.

Backlight

•

LED Lighting

LP8543 is available in the WQFN 24-pin package.

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2

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PRODUCTION DATA information is current as of publication date.

Copyright © 2009–2013, Texas Instruments Incorporated

Products conform to specifications per the terms of the Texas

Instruments standard warranty. Production processing does not

necessarily include testing of all parameters.