UNISONIC TECHNOLOGIES CO., LTD L5100 LINEAR INTEGRATED CIRCUIT WHITE LED STEP-UP CONVERTER DESCRIPTION The UTC L5100 is a STEP-UP DC/DC Converter and designed for driving white LEDs with a constant current. It can drive several LEDs in series by a Li-Ion cell. UTC L5100 switches at a high frequency 1.2MHz, so it can allow the use of tiny external components. The output capacitor can be as small as 0.22μF; saving space and cost compare with alternative other solutions. The low 95mV feedback voltage minimizes power loss in the current setting resistor can have better efficiency. FEATURES * Inherently Matched LED Current * High Efficiency: 83% Typical * Drives Up to Four LEDs from a 3.2V Supply * Drives Up to Six LEDs from a 5V Supply * 36V Rugged Bipolar Switch * 1.2MHz Switching Frequency * Uses Tiny 1mm Tall Inductors * Output Capacitor can be Small to only 0.22μF ORDERING INFORMATION Ordering Number L5100G-AF5-R Package SOT-25 Packing Tape Reel MARKING www.unisonic.com.tw Copyright © 2010 Unisonic Technologies Co., LTD 1 of 7 QW-R103-024.C L5100 LINEAR INTEGRATED CIRCUIT PIN CONFIGURATION PIN DESCRIPTION PIN NO. 1 2 PIN NAME SW GND 3 FB 4 SHDN 5 VIN DESCRIPTION Switch. Connect inductor/diode here. Minimize trace area at this pin to reduce EMI. Ground. Connect directly to local ground plane. Feedback. Reference voltage is 95mV. Connect cathode of lowest LED and resistor here. Calculate resistor value according to the formula: RFB = 95mV/ILED Shutdown. Connect to 1.5V or higher to enable device; 0.4V or less to disable device. Input Supply Pin. Must be locally bypassed. UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw 2 of 7 QW-R103-024.C L5100 LINEAR INTEGRATED CIRCUIT BLOCK DIAGRAM UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw 3 of 7 QW-R103-024.C L5100 LINEAR INTEGRATED CIRCUIT ABSOLUTE MAXIMUM RATINGS PARAMETER SYMBOL RATINGS UNIT Input Voltage VIN 12 V Switch Voltage VSW 36 V Feedback Voltage VFB 12 V V SHDN 12 V Shutdown Voltage Junction Temperature TJ +125 °C Operating Junction Temperature TJ -40~+85 °C Storage Temperature Range TSTG -65~+150 °C Note: Absolute maximum ratings are those values beyond which the device could be permanently damaged. Absolute maximum ratings are stress ratings only and functional device operation is not implied. THERMAL DATA PARAMETER Junction to Ambient (in free air) SYMBOL θJA RATINGS 256 UNIT °C/W ELECTRICAL CHARACTERISTICS (Ta=25°C, VIN=3V, V SHDN =3V, unless otherwise specified.) PARAMETER Operating Voltage Feedback Voltage Shutdown Voltage ON Shutdown Voltage OFF Switch VCESAT Switch Current Limit SYMBOL VIN VFB VON VOFF VCESAT(SW) ISW Supply current Switch Leakage Current Shutdown Pin Bias Current Feedback Pin Bias Current Switching Frequency Maximum Duty Cycle ICC ISW(OFF) ISHDN TEST CONDITIONS ISW=100mA, Duty Cycle=66% TYP 95 MAX 12 104 0.3 ISW=250mA SHDN =0V VSW=5V IFB fOSC DC UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw MIN 2.5 87 1.5 10 0.8 85 360 320 1.8 0.1 0.01 60 45 1.2 90 2.5 1.0 5 100 1.6 UNIT V mV V V mV mA mA µA µA µA nA MHz % 4 of 7 QW-R103-024.C L5100 EFFICIENCY (%) EFFICIENCY(%) TYPICAL APPLICATION CIRCUITS EFFICIENCY (%) LINEAR INTEGRATED CIRCUIT UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw 5 of 7 QW-R103-024.C L5100 TYPICAL APPLICATION CIRCUITS (Cont.) EFFICIENCY(%) LINEAR INTEGRATED CIRCUIT Seven LED Efficiency 85 V IN 5V L=22μH C IN 1µF D VDC DIMMING V IN C OUT 0. 22µF 80 SW 90k SHDN FB GND 75 5k R1 4Ω 70 5 V to Seven White LEDs UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw 65 0 1 0 LOAD CURRENT (mA) 1 5 5 6 of 7 QW-R103-024.C L5100 LINEAR INTEGRATED CIRCUIT TYPICAL CHARACTERISTICS Quiescent Current Current Limit vs Duty Cycle 350 2 .2 25 2 .0 300 1 .8 80 CURRENT LIMIT (mA) 1 .6 IQ (mA) 1 .4 1 .2 1 .0 0 .8 0 .6 0 .4 250 200 150 100 50 0 .2 0 0 0 2 4 6 8 10 V IN (V ) 0 20 40 60 80 100 DUTY CYCLE (%) * UTC L5100 is guaranteed the operating temperature range of 0°C ~ 75°C. UTC assumes no responsibility for equipment failures that result from using products at values that exceed, even momentarily, rated values (such as maximum ratings, operating condition ranges, or other parameters) listed in products specifications of any and all UTC products described or contained herein. UTC products are not designed for use in life support appliances, devices or systems where malfunction of these products can be reasonably expected to result in personal injury. Reproduction in whole or in part is prohibited without the prior written consent of the copyright owner. The information presented in this document does not form part of any quotation or contract, is believed to be accurate and reliable and may be changed without notice. UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw 7 of 7 QW-R103-024.C