UNISONIC TECHNOLOGIES CO., LTD L3012 LINEAR INTEGRATED CIRCUIT 1A HIGH POWER LED DRIVER WITH 4.5~40V INPUT DESCRIPTION The UTC L3012 is a step-down PWM control LED driver with a built-in power Switch. It achieves 1A continuous output current in 4.5~40V input voltage range. It has high efficiency up to more than 96%, with the excellent current accuracy within ±1%. FEATURES * 4.5~40V input voltage range * Maximum 1A output current * 0.15Ω built-in power MOSFET * 280kHz fixed frequency * Excellent constant current accuracy ±1% * Thermal shutdown * Cycle-by-cycle over current protection * PWM dimming function ORDERING INFORMATION Ordering Number L3012G-S08-R Package SOP-8 Packing Tape Reel L3012G-S08-R (1)Packing Type (1) R: Tape Reel (2)Package Type (2) S08: SOP-8 (3)Green Package (3) G: Halogen Free and Lead Free MARKING www.unisonic.com.tw Copyright © 2015 Unisonic Technologies Co., Ltd 1 of 5 QW-R125-025.D L3012 LINEAR INTEGRATED CIRCUIT PIN CONFIGURATION SW 1 8 ADJ GND 2 7 VDD SENSE 3 6 PWM VIN 4 PIN DESCRIPTION PIN NO. 1 2 3 4 5 6 7 8 5 COMP PIN NAME SW GND SENSE VIN COMP PWM VDD ADJ DESCRIPTION Power Switch output. Ground. Current sense pin. Input supply voltage. Compensation pin, connects to external capacitor. PWM dimming pin. 5V LDO output Thermal compensation pin or linear dimming pin. BLOCK DIAGRAM VIN SENSE COMP VDD 4 3 5 7 + Internal reference - 1 SW ADJ 8 Current setting OSC Osc S Vsense + PWM 6 Q Vgate M1 Driver R Current comparator PWM Control + Slope compensation - 3 GND UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw 2 of 5 QW-R125-025.D L3012 LINEAR INTEGRATED CIRCUIT ABSOLUTE MAXIMUM RATING (TA=25°C, unless otherwise specified) PARAMETER SYMBOL RATINGS UNIT Supply Voltage VIN 40 V Switch Voltage VSW -1~VIN+1 V Comp Voltage VCOMP -0.3~6 V SENSE Voltage VSENSE -0.3~VIN V Input Voltage VIN 4.5~40 V Junction Temperature TJ 150 °C Operating Temperature TOPR -40 ~ +125 °C Storage Temperature 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. ELECTRICAL CHARACTERISTICS (TA=25°C, unless otherwise specified, VIN=12V, IOUT=700mA) PARAMETER Supply Voltage Operating Current Upper Switch Leakage Current Limit Maximum Duty Cycle Oscillator Frequency COMP Clamp Voltage Switch Transistor on Resistance Sampling Voltage Threshold Thermal Shutdown Threshold Thermal Shutdown Hysteresis SYMBOL VIN IIN IL ILIM DMAX fOSC VCOMP RON VIN-VSENSE TSD TSD-hys TEST CONDITIONS VCC=4/40V (Switch Off) VSW=40V VIN=SENSE=12V 3LED, VIN=9V 1.7 250 Open without load 1LED, IOUT=1A Drop voltage between VIN and SENSE UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw MIN 6 TYP 2.2 0 2 94 280 2.6 0.15 100 160 30 MAX 36 5 5 3 96 350 0.5 UNIT V mA μA A % kHz V Ω mV °C °C 3 of 5 QW-R125-025.D L3012 LINEAR INTEGRATED CIRCUIT FUNCTION DESCRIPTION The UTC L3012 is a current mode and fixed frequency (280kHz) LED driver. 1. Output current setting The output current is determined by the sampling resistor (RS) and setting voltage (VIN-VSENSE a built-in fixed 100mV). V VSENSE I OUT IN =100mV/Rs RS 2. Current limiting UTC L3012 has internal current limiting function, and the voltage on COMP is clamped at about 2V, the output current of the power MOSFET is limited at about 2A by current comparator. 3. Diode Selection UTC L3012 driver LED need a Schottky diode. If output current is 700mA or smaller then SS14W (1N5819) is ok. The average current through the diode is ID: ID= (1-D)·ILED ILED is the current of LED 4. PWM dimming UTC L3012 has internal PWM dimming function. When PWM voltage is connects to high level, the chip is working normally, when PWM voltage is open or connects to low level, the COMP pin voltage will keep normal state, so can improve the startup speed of the chip. Adjust the output current by control the duty of external PWM signal. The minimum setup time of UTC L3012 PWM dimming is less than 20μS, and the maximum PWM dimming ratio is up to 500:1. When high dimming ratio is needed, the dimming frequency is recommended 500Hz below, or else the dimming frequency can be up to 2KHz. When PWM pin is low, output is shutdown. TYPICAL APPLICATION CIRCUI L SBD Cout 1 SW ADJ 8 2 GND VDD 7 3 SENSE PWM 6 4 VIN COMP 5 Rs VIN 10µF UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw 100nF 1µF 4 of 5 QW-R125-025.D L3012 LINEAR INTEGRATED CIRCUIT 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 5 of 5 QW-R125-025.D