LM27966 Datasheet | National Semiconductor

Description The LM27966 is a highly integrated charge-pump-based display LED driver. The device can drive up to 6 LEDs in parallel with a total output current of 180m A. Regulated internal current sources deliver excellent current and brightness matching in all LEDs. The LED driver current sources are split into two independently controlled groups. The primary group, which can be .. configured with 4 or 5 LEDs, can be used to backlight the main phone display. An additional, independently controlled led driver is provided for driving an indicator or other general purpose LED function. The LM27966 has an I2C patible interface that allows the user to independently control the brightness on each bank of LEDs. The device provides excellent efficiency without the use of an inductor by operating the charge pump in a gain of 3/2, or in Pass-Mode. The proper gain for maintaining current regulation is chosen, based on LED forward voltage, so that efficiency is maximized over the input voltage range. The LM27966 is available in National’s small 24-pin Leadless Leadframe Package (LLP-24). Features n n n n n n n n n n n 91% Peak LED Drive Efficiency No Inductor Required 0.3% Current Matching Drives 6 LEDs with up to 30m A per LED 180m A of total driver current I2C patible Brightness Control Interface Adaptive 1x- 3/2x Charge Pump Resistor-Programmable Current Settings External Chip RESET Pin (RESET) Extended Li-Ion Input: 2.7V to 5.5V Small low profile industry standard leadless package, LLP 24 : (4mm x 4mm x 0.8mm) Applications n Mobile Phone Display Lighting n PDAs Backlighting n General LED Lighting Typical Application Circuit © 2006 National Semiconductor Corporation DS201901 .national. Connection Diagram 24 Pin Quad LLP Package NS Package Number SQA24A .. Pin Descriptions Pin #s 24 23 19, 22 (C1) 20, 21 (C2) 12, 13, 14, 15, 16 3 17 Pin Names VIN POUT C1, C2 D5, D4, D3, D2, D1 DAUX ISET Charge Pump Output Voltage Flying Capacitor...