LP8545

www.ti.com

SNVS635D – APRIL 2010 – REVISED DECEMBER 2013

High-Efficiency LED Backlight Driver for Notebooks

Check for Samples: LP8545

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FEATURES

DESCRIPTION

The LP8545 is a white LED driver with integrated

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•

High-Voltage DC/DC Boost Converter with

boost converter. It has six adjustable current sinks

Integrated FET with Four Switching Frequency

Options: 156/312/625/1250 kHz

compatible serial interface.

•

Configurable for Use with External FET for

The boost converter has adaptive output voltage

Applications Needing Higher Output Voltage

control based on the LED driver voltages. This

•

2.7V – 22V Input Voltage Range to Support

feature

minimizes

the

power

consumption

by

1x…5x Cell Li-Ion Batteries

adjusting the voltage to lowest sufficient level in all

•

Programmable PWM Resolution

conditions.

–

8 to 13 True Bit (Steady State)

LED outputs have 8-bit current resolution and up to

13-bit PWM resolution with additional 1-3 bit dithering

–

Additional 1 to 3 Bits Using Dithering

to achieve smooth and precise brightness control.

During Brightness Changes

Proprietary Phase Shift PWM control is used for LED

•

outputs to reduce peak current from the boost

•

PWM Output Frequency and LED Current Set

converter, thus making the boost capacitors smaller.

Through Resistors

The Phase Shifting scheme also eliminates audible

noise.

•

Signal

Internal EEPROM is used for storing the configuration

data. This makes it possible to have minimum

•

6 LED Outputs with LED fault (Short/Open)

external component count and make the solution very

Detection

small.

•

Low Input Voltage, Over-Temperature, Over-

Current Detection and Shutdown

LP8545 has safety features which make it possible to

detect LED outputs with open or short fault. As well

•

Minimum Number of External Components

low input voltage and boost over-current conditions

•

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

are monitored and chip is turned off in case of these

events.

Thermal

de-rating

function

prevents

APPLICATIONS

overheating of the device by reducing backlight

brightness when set temperature has been reached.

•

Notebook and Netbook LCD Display LED

Backlight

LP8545 is available in TI's WQFN 24-pin package.

•

LED Lighting

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Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.

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PRODUCTION DATA information is current as of publication date.

Copyright © 2010–2013, 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.