unisonic technologies co., ltd l3010 preliminary linear integrated circuit www.unisonic.com.tw 1 of 5 copyright ? 2012 unisonic technologies co., ltd qw-125-024.a 1a high power led driver with 4.5~40v input ? description the utc l3010 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 * 0.25 ? built-in power mosfet * 280khz fixed frequency * excellent constant cu rrent accuracy 1% * high efficiency up to 96% * thermal shutdown * cycle-by-cycle over current protection ? ordering information ordering number package packing lead free halogen free l3010l-s08-r l3010g-s08-r sop-8 tape reel l3010l-s08-t L3010G-S08-T sop-8 tube (1) r: tape reel, t: tube (2) s08: sop-8 (3) g: halogen free, l: lead free l3010l-s08-r (1)packing type (2)package type (3)lead free
l3010 preliminary linear integrated circuit unisonic technologies co., ltd 2 of 5 www.unisonic.com.tw qw-r125-024.a ? pin configuration 1 2 3 4 8 7 6 5 sw gnd sense v in nc nc nc comp ? pin description pin no. pin name description 1 sw power switch output. 2 gnd ground. 3 sense current sense pin. 4 v in input supply voltage. 5 comp compensation pin, connec ts to external capacitor. 6~8 nc no connected. ? block diagram 4 v in 2 gnd 1 sw + - driver nmos reference s q r rsense current sense + + + - uvlo 280khz slope comp otp ss + - comp 5 snese 3 ea pwm 88mv
l3010 preliminary linear integrated circuit unisonic technologies co., ltd 3 of 5 www.unisonic.com.tw qw-r125-024.a ? absolute maximum rating (unless otherwise specified ) parameter symbol ratings unit supply voltage v in 43 v switch voltage v sw -1~v in +1 v comp voltage v comp -0.3~6 v sense voltage v sense -0.3~v in v input voltage v in 4.5~40 v junction temperature t j 150 c operating temperature t opr -40 ~ +125 c storage temperature t stg -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 oper ation is not implied. ? electrical characteristics (t a =25c, unless otherwise specified, v in =12v, i out =700ma) parameter symbol test conditions min typ max unit supply voltage v in 4.5 40 v operating current i in v cc =4/40v (switch off) 2.2 4 ma upper switch leakage i l v sw =40v 0 5 a current limit i lim v in =sense=12v 1.7 2.1 3 a maximum duty cycle d max 3led, v in =9v 94 96 % oscillator frequency f osc 250 280 320 khz comp clamp voltage v comp open without load 1.6 2 2.2 v switch transistor on resistance r on 1led, i out =1a 0.25 0.5 ? sampling voltage threshold v in -v sense drop voltage between v in and sense 88 mv thermal shutdown threshold tsd 160 c thermal shutdown hysteresis tsd-hys 30 c
l3010 preliminary linear integrated circuit unisonic technologies co., ltd 4 of 5 www.unisonic.com.tw qw-r125-024.a ? function description the utc l3010 is a current mode and fixed frequency (280khz) led driver. 1. output current setting the output current is determined by the sampling resistor (r s ) and setting voltage (v in -v sense a built-in fixed 88mv). s sense in out r v v i ? = =88mv/rs 2. current limiting utc l3010 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 2.1a by current comparator. ? components selection 1. input capacitor selection this capacitor should be located close to the ic usin g short leads. the rms current rating requirement for the input capacitor of a buck regulator is approximately 1 2 the dc load current. a low esr input capacitor sized for maximum rms current must be used. it is recommend use the mlcc capacitor of 10 f or larger. 2. output capacitance selection the output capacitor is required to filter the output reduce the ripple current of led and provide regulator loop stability. the important capaci tor parameters are; the 100khz equivalent series resistance (esr), the rms ripples current rating, voltage rating, and capacitance value. for the output capacitor, the esr value is the most important parameter. it is recommend use the mlcc capacitor of 2.2 f or larger. 3. inductance selection for most designs, the operates with inductors of 47 h to 68 h. where is inductor ripple current. large value inductors lower ripple current and small value inductors result in high ripple currents. the dc current rating of the inductor should be at least equal to the maximum load current plus half the ripple current to prevent core saturation. in order to improve the efficiency, the series-wound re sistor (dcr) of inductance should be smaller than 0.2 ? . the inductor value can be derived from the following equation: osc l in out in out f i v ) v v ( v l ? = where: l: inductance value f: oscillator frequency i is ripple current 4. diode selection utc l3010 driver led need a schottky diode. if output current is 700ma or smaller then ss14 (d1n5819) is ok. the average current through the diode is i d : i d = (1-d) i led i led is the current of led
l3010 preliminary linear integrated circuit unisonic technologies co., ltd 5 of 5 www.unisonic.com.tw qw-r125-024.a ? typical application circuit note: the circuit and parameters are reference only, please set the parameters of the real application circuit based on the real test . 4.5~40v input voltage, 350ma output led driver rs 0.25 2.2f + 47h 1 5 gnd v in comp sw utc l3010 v in c in 10f + 4 100nf 2 sense 3 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.
|
