LTC3230 5-LED Main/Sub Display Driver with Dual LDO FEATURES DESCRIPTION Low Noise Charge Pump Provides High Ef ciency The LTC 3230 is a low noise charge pump DC/DC converter with Automatic Mode Switching designed to drive 4 Main LEDs and 1 Sub LED, plus two Multimode Operation: 1x, 1.5x, 2x 200mA linear regulators to provide additional system Full-Scale Current Set Resistor power. The LTC3230 charge pump requires only four small Up to 125mA Total LED Current ceramic capacitors and one current set resistor to form a Single Wire Enable/Brightness Control for Main and complete LED power supply and current controller. Sub Display LEDs Built-in soft-start circuitry prevents excessive inrush cur- 32:1 Linear LED Brightness Control rent during start-up and mode changes. High switching Dual 200mA Linear Regulators frequency enables the use of small external capacitors. Four 25mA Low Dropout Main LED Current Sources Main and Sub full-scale current settings are programmed One 25mA Low Dropout Sub LED Current Source by a single external resistor. Low Noise Constant Frequency Operation Charge pump ef ciency is optimized based on the voltage Low Shutdown Current: 3A across the LED current sources. The part powers up in 1x Internal Soft-Start Limits Inrush Current During mode and automatically switches to the next higher mode, Start-Up and Mode Switching 1.5x and subsequently 2x, whenever any LED current Open/Short LED Protection source approaches dropout. No Inductors 20-Lead 3mm 3mm QFN Package Two 200mA linear regulators have independent enable and output voltage select pins. Each regulator can be set APPLICATIONS to one of three pre-selected output voltages with tri-level input pins. The regulators may be enabled independently Multi-LED Driver and Dual LDO Supplies for Cell of the charge pump. Phone, PDA, Digital Camera and PND Applications , LT, LTC and LTM are registered trademarks of Linear Technology Corporation. The LTC3230 is available in a low pro le (0.75mm) 3mm All other trademarks are the property of their respective owners. Protected by U.S. Patents including 6411531. 3mm 20-lead QFN package. TYPICAL APPLICATION C1 C2 1 F 1 F Ef ciency vs V Voltage IN 100 90 125mA C1P C1M C2P C2M MAIN SUB V = 2.7V 80 IN V CPO IN TO 5.5V C3 C6 70 2.2 F LTC3230 1 F D1 D2 D3 D4 D5 60 ENM ENM MLED1 ENS ENS MLED2 50 MLED3 MLED4 40 ENLDO1 SLED 3230 TA01a 30 ENLDO2 LDO1 1.5V C4 V1 200mA 20 1 F 4 LEDs AT 9mA/LED V2 V = 3V R LDO2 2.8V SET 10 F R GND SET C5 T = 25C 200mA A 17.4k 1 F 0 1% 3 3.2 3.4 3.6 3.8 4 4.2 4.4 V (V) IN ENM OR ENS 3230 TA01b SET BRIGHTNESS LEVEL ON OFF 3230fa 1 EFFICIENCY (P /P ) (%) LED INLTC3230 ABSOLUTE MAXIMUM RATINGS PIN CONFIGURATION (Notes 1-5) TOP VIEW V , CPO ....................................................... 0.3V to 6V IN ENM, ENS, ENLDO1, ENLDO2, 20 19 18 17 16 V1, V2, LDO1, LDO2 ......................0.3V to (V + 0.3V) IN CPO 1 15 LDO1 I (Note 2) ........................................................200mA CPO ENLDO1 2 14 LDO2 LD01, LD02 (Note 3) ............................................200mA ENLDO2 3 21 13 V1 MLED1-4, SLED, R .................................. 0.3V to 6V R 4 12 V2 SET SET ENS 5 11 ENM Operating Ambient Temperature Range 6 7 8 9 10 (Note 4) .................................................... 40C to 85C Junction Temperature ........................................... 125C Storage Temperature Range ................... 65C to 150C UD PACKAGE 20-LEAD (3mm 3mm) PLASTIC QFN T = 125C, = 68C/W JMAX JA EXPOSED PAD (PIN 21) IS GND, MUST BE SOLDERED TO PCB ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL PART MARKING PACKAGE DESCRIPTION TEMPERATURE RANGE LTC3230EUD PBF LTC3230EUD TRPBF LCYB 20-Lead (3mm 3mm) Plastic QFN 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: