LP5520 Datasheet | National Semiconductor

Description The LP5520 is an RGB backlight LED driver for small format color LCDs. RGB backlight enables better colors on the display and power savings pared with white LED backlight. LP5520 offers small and simple driver solution without need for optical feedback. Calibration in display module production can be done in one temperature. LP5520 produces true white light over 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 up to 20V LED supply voltage from the battery voltage. The output can be set at 1V step from 5V to 20V. 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 e.g. for ambient light measurement. LP5520 is available in 25 pin micro SMD™ package. Features - - - - - - - - - - - - - - - Temperature pensated 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 R, G and B LED 0.2% typical LED output current matching PWM control inputs for each color SPI and I2C patible interface Stand-alone mode with 1 wire control Sequential mode for one color at a time Magnetic high efficiency boost converter Programmable output voltage from 5V to 20V Adaptive output voltage control option < 2 µA typical shutdown current Micro SMD-25 package, 2.77 ×...