LT3591EDDB#TRMPBF Analog Devices

LT3591 White LED Driver with Integrated Schottky in 3mm 2mm DFN FEATURES DESCRIPTION Drives Up to Ten White LEDs from a 3V Supply The LT 3591 is a xed frequency step-up DC/DC converter High Side Sense Allows One Wire Current Source speci cally designed to drive up to ten white LEDs in series Internal Schottky Diode from a Li-Ion cell. Series connection of the LEDs provides One Pin Dimming and Shutdown identical LED currents resulting in uniform brightness TM 80:1 True Color PWM Dimming Range and eliminating the need for ballast resistors. The device 42V Open LED Protection features a unique high side LED current sense that enables 1MHz Switching Frequency the part to function as a one wire current source one 5% Reference Accuracy side of the LED string can be returned to ground anywhere, V Range: 2.5V to 12V allowing a simpler one wire LED connection. Traditional IN Requires Only 2.2F Output Capacitor LED drivers use a grounded resistor to sense LED current, Low Pro le 8-Lead DFN Package requiring a 2-wire connection to the LED string. (3mm 2mm 0.75mm) The high switching frequency allows the use of tiny induc- tors and capacitors. A single pin performs both shutdown and accurate LED dimming control. Few external compo- APPLICATIONS nents are needed: open-LED protection and the Schottky Cellular Phones diode are all contained inside a low pro le 3mm 2mm PDAs, Handheld Computers DFN package. Digital Cameras , LT, LTC and LTM are registered trademarks of Linear Technology Corporation. MP3 Players True Color PWM is a trademark of Linear Technology Corporation. All other trademarks are the property of their respective owners. GPS Receivers TYPICAL APPLICATION Li-Ion Driver for Ten White LEDs Conversion Ef ciency 80 SHUTDOWN AND V = 3.6V IN DIMMING CONTROL 10 LEDs 75 CTRL V IN V CAP IN 3V TO 5V 70 R SENSE 22H LT3591 10 SW LED 65 GND 2.2F 1F 60 55 0 5 10 15 20 LED CURRENT (mA) 3591 TA01b 3591 TA01a 3591f 1 EFFICIENCY (%)LT3591 ABSOLUTE MAXIMUM RATINGS PACKAGE/ORDER INFORMATION (Note 1) TOP VIEW Input Voltage (V ) ................................................... 12V IN CTRL Voltage ........................................................... 12V V 1 8 CTRL IN SW Voltage .............................................................. 45V GND 2 7 LED 9 NC 3 6 NC CAP Voltage ............................................................. 45V SW 4 5 CAP LED Voltage ............................................................. 45V Operating Junction Temperature Range DDB PACKAGE (Note 2) ...............................................40C to 85C 8-LEAD (3mm 2mm) PLASTIC DFN T = 125C, = 76C/W Maximum Junction Temperature ........................ 125C JMAX JA EXPOSED PAD (PIN 9) SHOULD BE CONNECTED TO PCB GROUND Storage Temperature Range ...................65C to 150C ORDER PART NUMBER DDB PART MARKING LT3591EDDB LCPG Order Options Tape and Reel: Add TR Lead Free: Add PBF Lead Free Tape and Reel: Add TRPBF Lead Free Part Marking: