1 Features

1? Temperature Compensated LED Intensity and

Color

? Individual Calibration Coefficients for Each Color

? Color Accuracy ΔX and ΔY ≤ 0.003

? 12-Bit ADC for Measurement of 2 Sensors

? Adjustable Current Outputs for Red, Green, and

Blue (RGB) LED

? 0.2% Typical LED Output Current Matching

? PWM Control Inputs for Each Color

? SPI? and I2C-Compatible Interface

? Stand-Alone Mode With One-Wire Control

? Sequential Mode for One Color at a Time

? Magnetic High Efficiency Boost Converter

? Programmable Output Voltage from 5 V to 20 V

? Adaptive Output Voltage Control Option

? < 2-μA Typical Shutdown Current

2 Applications

? Color LCD Display Backlighting

? LED Lighting Applications

3 Description

The LP5520 is an RGB backlight LED driver for small

format color LCDs. RGB backlights enable better

colors on the display and power savings compared

with white LED backlights. The device offers a small

and simple driver solution without need for optical

feedback. Calibration in display module production

can be done in one temperature. The LP5520

produces true white light over a wide temperature

range. Three independent LED drivers have accurate

programmable current sinks and PWM modulation

control. Using internal calibration memory and

external temperature sensor, the RGB LED currents

are adjusted for perfect white balance independent of

the brightness setting or temperature. The user

programmable calibration memory has intensity vs

temperature data for each color. This white balance

calibration data can be programmed to the memory

on the production line of a backlight module.

The device has a magnetic boost converter that

creates a supply voltage of up to 20 V LED from the

battery voltage. The output can be set at 1-V steps

from 5 V to 20 V. In adaptive mode the circuit

automatically adjusts the output voltage to minimum

sufficient level for lowest power consumption.

Temperature is measured using an external

temperature sensor placed close to the LEDs. The

second ADC input can be used, for example, for

ambient light measurement.