LT3466-1 White LED Driver and Boost Converter in 3mm 3mm DFN Package FEATURES DESCRIPTIO Drives Up to 10 White LEDs from a 3.6V Supply LT 3466-1 is a dual switching regulator that combines a Two Independent Step-Up DC/DC Converters white LED driver and a boost converter in a low profile, Independent Dimming and Shutdown Control small footprint (3mm 3mm 0.75mm) DFN package. of the Outputs The LED driver can be configured to drive up to 10 White 1.5% Output Voltage Accuracy (Boost Converter) LEDs in series and the boost converter can be used for 4% LED Current Programming Accuracy generating the LCD bias voltages or driving a secondary Internal Schottky Diodes OLED display. Series connection of the LEDs provides Internal Soft-Start Eliminates Inrush Current identical LED currents resulting in uniform brightness and Output Overvoltage Protection (39.5V Max V ) eliminating the need for ballast resistors and expensive OUT Fixed Frequency Operation Up to 2MHz factory calibration. 83% Efficiency Driving 8 White LEDs at 15mA The LT3466-1 provides independent dimming and shut- from a 3.6V Supply down control of the two converters. The operating fre- Wide Input Voltage Range: 2.7V to 24V quency can be set with an external resistor over a 200kHz Tiny (3mm 3mm) 10-Lead DFN Package to 2MHz range. The white LED driver features a low 200mV reference, thereby minimizing power loss in the current U setting resistor for better efficiency. The boost converter APPLICATIO S achieves 1.5% output voltage accuracy by the use of a White LED and OLED Displays precision 0.8V reference. Protection features include out- Digital Cameras, Sub-Notebook PCs put overvoltage protection and internal soft-start. Wide PDAs, Handheld Computers input supply range allows operation from 2.7V to 24V. TFT - LCD Bias Supply , LTC and LT are registered trademarks of Linear Technology Corporation. Automotive All other trademarks are the property of their respective owners. TYPICAL APPLICATIO 3V TO 5V Conversion Efficiency 1F 90 33H 33H V = 3.6V IN 85 LED DRIVER SW1 V SW2 IN 80 BOOST CONVERTER 75 16V 6 LEDs 70 V V LT3466-1 OUT1 OUT2 30mA 1F1F 65 475k FB1 FB2 60 R CTRL1 GND CTRL2 T 55 63.4k 50 SHUTDOWN SHUTDOWN 10 24.9k 0 510 15 20 25 30 AND DIMMING AND DIMMING CONTROL 1 CONTROL 2 OUTPUT CURRENT (mA) 34661 F01a 34661 F01b Figure 1. Li-Ion Powered Driver for 6 White LEDs and OLED Display 34661f 1 EFFICIENCY (%) U ULT3466-1 UUW ABSOLUTE AXI U RATI GS PACKAGE/ORDER I FOR ATIO (Note 1) TOP VIEW Input Voltage (V ) ................................................... 24V ORDER PART IN SW1, SW2 Voltages ................................................ 44V NUMBER 10 V 1 FB1 OUT1 V , V Voltages ............................................. 44V OUT1 OUT2 SW1 2 9 CTRL1 LT3466EDD-1 11 CTRL1, CTRL2 Voltages ........................................... 24V V 3 8 R IN T SW2 4 7 CTRL2 FB1, FB2 Voltages ...................................................... 2V V 5 6 FB2 OUT2 Operating Temperature Range (Note 2) ... 40C to 85C DD PART MARKING Storage Temperature Range .................. 65C to 125C DD PACKAGE 10-LEAD (3mm 3mm) PLASTIC DFN Junction Temperature .......................................... 125C T = 125C, = 43C/W, = 3C/W JMAX JA JC LBRX EXPOSED PAD (PIN 11) IS GND MUST BE SOLDERED TO PCB Order Options Tape and Reel: Add TR Lead Free: Add PBF Lead Free Tape and Reel: Add TRPBF Lead Free Part Marking: