LM3533

Product Folder Sample & Buy Technical Documents Tools & Software Support & Community LM3533 SNOSC68C – APRIL 2012 – REVISED SEPTEMBER 2015 LM3533 Complete Lighting Power Solution for Smartphone Handsets 1 Features 1 Drives Two Parallel High-Voltage LED Strings for Display and Keypad Lighting High-Voltage Strings Capable of up to 40-V Output Voltage and up to 90% Efficiency Up to 30 mA per Current Sink (Both Backlight and Indicator) 14-Bit Equivalent Exponential Dimming With 8-Bit Programmable Backlight Code Selectable Analog ALS Input with 128 Programmable Gain-Setting Resistors or PWM ALS Input With Internal Low-Pass Filter PWM Input for Content Adjustable Brightness Control Five Low-Voltage Current Sinks for Indicator LEDs Integrated Charge Pump for Improved Efficiency and VIN Operating Range Internal Pattern Generation Engine Fully Configurable LED Grouping and Control Four Programmable Overvoltage Protection Thresholds (16 V, 24 V, 32 V, and 40 V) Programmable 500-kHz and 1-MHz Switching Frequency 27-mm2 Total Solution Size 2 Applications Power Source for Smart Phone Illumination Display, Keypad and Indicator Illumination RGB Indicator Driver 3 Description The LM3533 is a complete power source for backlight, keypad, and indicator LEDs in smartphone handsets. The high-voltage inductive boost converter provides the power for two series LED strings for display backlight and keypad functions (HVLED1 and HVLED2). The integrated charge pump...