LTC3216 1A Low Noise High Current LED Charge Pump with Independent Torch/Flash Current Control FEATURES DESCRIPTION n High Ef ciency Operation: 1x, 1.5x or 2x Boost The LTC 3216 is a low noise, high current charge pump Modes with Automatic Mode Switching DC/DC converter designed to power high current LEDs. n Ultralow Dropout I Current Control The part includes an accurate programmable current LED n Output Current up to 1A source capable of driving loads up to 1A from a 2.9V to n Low Noise Constant Frequency Operation 4.4V input. Low external parts count (two ying capacitors, n Independent Low Current/High Current two programming resistors and two bypass capacitors at Programming and Enable Pins V and CPO) make the LTC3216 ideally suited for small, IN n Wide V Range: 2.9V to 4.4V battery-powered applications. IN n Open/Shorted LED Protection Built-in soft-start circuitry prevents excessive inrush cur- n LED Disconnect in Shutdown rent during start-up. High switching frequency enables n Low Shutdown Current: 2.5A the use of small external capacitors. Independent high n 4% LED Current Programming Accuracy and low current settings are programmed by two external n Automatic Soft-Start Limits Inrush Current resistors. Shutdown mode and current output levels are n No Inductors selected via two logic inputs. n Tiny Application Circuit (All Components <1mm An ultralow dropout current source maintains accurate Pro le) n LED current at very low I voltages. Automatic mode 3mm 4mm 12-Lead DFN Package LED switching optimizes ef ciency by monitoring the voltage APPLICATIONS across the LED current source and switching modes only when I dropout is detected. The LTC3216 is available LED n LED Torch/Camera Light Supply for Cell Phones, in a small 3mm 4mm 12-Lead DFN package. PDAs and Digital Cameras L, LT, LTC and LTM are registered trademarks of Linear Technology Corporation. n Generic Lighting and/or Flash/Strobe Applications All other trademarks are the property of their respective owners. Protected by U.S. Patents including 6411531. TYPICAL APPLICATION Torch Mode Ef ciency vs V IN C1 C2 2.2F 2.2F 100 90 I = 200mA LED + + 80 C1 C1 C2 C2 V CPO 70 2.9V TO 4.4V IN C C IN CPO 60 2.2F 4.7F LTC3216 50 LED1 I 40 LED EN1 (TORCH) EN1 30 EN2 (FLASH) EN2 20 P /PIN LED I I I LED SET1 SET2 EN1 EN2 LUMILEDS LXCL-PWF1 10 0 0 0 (SHUTDOWN) V = 3V TYP AT 200mA F 20k 6.65k 1 0 200mA (TORCH) 0 2.8 3.6 4.0 4.2 1% 1% 0 1 600mA 3.0 3.2 3.4 3.8 4.4 1 1 800mA (FLASH) V (V) IN 3216 TA01a 3216 TA01b LED1: LUMILEDS LXCL-PWF1 LUXEON FLASH 3216fc 1 EFFICIENCY (P /PIN) (%) LEDLTC3216 ABSOLUTE MAXIMUM RATINGS PIN CONFIGURATION (Note 1) TOP VIEW V to GND ................................................ 0.3V to 5.5V IN + C2 1 12 C1 CPO to GND .............................................. 0.3V to 5.5V + C1 2 11 GND EN2, EN1 ...........................................0.3V to V + 0.3V IN CPO 3 10 C2 I , I (Note 2) .............................................1500mA CPO ILED 13 I 4 9 VIN SET1 CPO Short-Circuit Duration .............................. Inde nite I 5 8 EN2 LED Operating Temperature Range (Note 3).... 40C to 85C I 6 7 EN1 SET2 Storage Temperature Range ................... 65C to 125C DE12 PACKAGE 12-LEAD (4mm 3mm) PLASTIC DFN EXPOSED PAD IS GND (PIN 13) MUST BE SOLDERED TO PCB T = 125C, = 43C/W JMAX JA ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL PART MARKING PACKAGE DESCRIPTION TEMPERATURE RANGE LTC3216EDE PBF LTC3216EDE TRPBF 3216 12-Lead (4mm 3mm) Plastic DFN 40C to 85C Consult LTC Marketing for parts speci ed with wider operating temperature ranges. Consult LTC Marketing for information on non-standard lead based nish parts. For more information on lead free part marking, go to: