unisonic technologies co., ltd LR18120 cmos ic www.unisonic.com.tw 1 of 8 copyright ? 2009 unisonic technologies co., ltd qw-r502-305.a 2a low dropout regulator with enable ? description the utc LR18120 is a positive voltage regulator with high performance. it has low dropout voltage and low input voltage, besides its output voltage can be fix ed at 1.2v, 1.5v, 1.8v, or 2.5v depending on internal feedback resistors or adj (not connected to the ground) with external feedback resi stors. the input voltage of utc LR18120 can be low to 1.4v. there are two additional pin in the LR18120. one is en pin a nd the other is pok pin. the utc LR18120 is specially made for applications with low input voltage, low dropout voltage, and low output voltage which is almost the same as the input volt age. typical applications include motherboards, notebooks, set top boxes, network cards and peripheral cards. ? features * v in as low as 1.4v and v pp voltage 5v * v d =320mv @ i o =2a, v o =1.2v * internal over current and over temperature protection * with enable pin * output voltage: 2% * 1.2v, 1.5v, 1.8v and 2.5v output voltage adjustable external ly using resistors * when disable v o pull low resistance lead-free: LR18120l-xx halogen-free:LR18120g-xx ? ordering information ordering number normal lead free plating halogen free package packing LR18120-xx-s08-r LR18120l-xx-s08-r lr 18120g-xx-s08-r sop-8 tape reel LR18120-xx-sh2-r LR18120l-xx-sh2-r LR18120g-xx-sh2-r hsop-8 tape reel
LR18120 cmos ic unisonic technologies co., ltd 2 of 8 www.unisonic.com.tw qw-r502-305.a ? pin configuration pok v en v in v pp nc v o adj gnd 1 3 45 6 8 7 sop-8/hsop-8 2 ? pin description pin no. pin name description 1 pok this pin will indicate high under this situation: v o reaches 92% of its rating voltage. open-drain output. 2 v en the enable control input pin. as while as this pin?s voltage falls below 0.4v ,the LR18120 will stop working. when there?s nothing connected with this pin,the device will be enabled. 3 v in the pin of input voltage. placing large capacitance closely to th is pin is necessary. there should be connected a 10f ceramic capacitor. 4 v pp this pin is for input voltage to control circuit. 5 nc connected nothing. 6 v o the voltage output pin. 7 adj when this pin connected to the ground,v out will be set by the internal feedback resistors. otherwise, if using external feedback resistors to decide the v out , v out = 0.8(r1+r2)/r2 volts. 8 gnd ground.
LR18120 cmos ic unisonic technologies co., ltd 3 of 8 www.unisonic.com.tw qw-r502-305.a ? block diagram + - + -
LR18120 cmos ic unisonic technologies co., ltd 4 of 8 www.unisonic.com.tw qw-r502-305.a ? absolute maximum rating parameter symbol ratings unit input voltage v pp , v in 7 v power dissipation p d internally limited junction temperature t j 150 c operation temperature t opr -40~ +85 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. ? recommended operating conditions parameter symbol ratings unit v in voltage v in 1.4 ~5.5 v v pp voltage v pp 4.5~5.5 v temperature range t a -40c t a +85c c ? thermal data parameter symbol ratings unit sop-8 150 c/w junction to ambient hsop-8 ja 143 c/w sop-8 20 c/w junction to case hsop-8 jc 14 c/w ? electrical characteristics v pp =5v, v in =3.3v, v en =v pp , i out =10ma, c in =10f, c out =10f, t a =t j =25c unless otherwise specified. parameter symbol test conditions min typ max unit v in input voltage range v in 1.4 5.5 v quiescent current (ground current) i q v out =2.5v 1 2 ma v pp v pp voltage range v pp 4.5 5.5 v i pph v out =2.5v 0.23 0.5 ma v pp current i ppl v en =0v 36 60 a v out output voltage (inter nal fixed voltage) v out v in = v out +0.5v, v out =2.5v 2.45 2.5 2.55 v line regulation out in out v v v v in =( v out +0.5v) ~ 5v 0.2 1 % load regulation v out 10ma i out 2a 0.2 1 % dropout voltage v d i out =2a 250 320 mv short circuit current 1.4 a v out pull low resistance v en =0v 90 ? adj reference voltage v ref v adj = v out 0.788 0.8 0.812 v adjust pin current i adj 20 100 na adjust pin threshold 0.15 0.2 0.25 v ven v en pin voltage high v h(en) 1.6 v v en pin voltage low v l(en) 0.4 v v en pin bias current i bias(en) v en =0v 12 40 a pok v out power ok voltage v thpok 92 % hysteresis v hypok 7 % over temperature protection over temperature t ot 150 c over temperature hysteresis t othy 30 c note: low duty pulse techniques are used during test to maintain junction temperature as close to ambient as possible.
LR18120 cmos ic unisonic technologies co., ltd 5 of 8 www.unisonic.com.tw qw-r502-305.a ? typical application circuit r2 r2) + 0.8(r1
LR18120 cmos ic unisonic technologies co., ltd 6 of 8 www.unisonic.com.tw qw-r502-305.a ? typical characteristics (v cc = 3.3v, t a =25c, unless otherwise noted.) 3 3.5 4 4.5 5 5.5 input voltage, v in (v) 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 quiescent current, i q (ma) quiescent current vs. input voltage 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 quiescent current, i q (ma) -45-35 -25-15 -5 5 15 25 35 45 55 65 75 85 temperature (c) quiescent current vs. temperature 3 3.5 4 4.5 5 5.5 input voltage, v in (v) 0 0.1 0.05 0.15 0.2 0.25 0.3 0.35 0.4 0.45 0.5 ipph current, i ipph (ma) ipph current vs. input voltage -45-35-25-15 -5 5 15 25 35 45 55 65 75 85 temperature (c) 0 0.1 0.05 0.15 0.2 0.25 0.3 0.35 0.4 0.45 0.5 ipph current, i ipph (ma) ipph current vs. temperature 3 3.5 4 4.5 5 5.5 input voltage, v in (v) 0 5 10 15 20 25 30 35 40 ippl current, i ippl (a) ippl current vs. input voltage -45-35-25-15 -5 5 15 25 35 45 55 65 75 85 temperature (c) 0 5 10 15 20 25 30 35 40 ippl current, i ippl (a) ippl current vs. temperature
LR18120 cmos ic unisonic technologies co., ltd 7 of 8 www.unisonic.com.tw qw-r502-305.a ? typical characteristics(cont.) 3 3.5 4 4.5 5 5.5 input voltage, v in (v) 2.45 2.46 2.47 2.48 2.49 2.5 2.51 2.52 2.53 2.54 2.55 output voltage, v o (v) output voltage vs. input voltage i o =0a 3 3.5 4 4.5 5 5.5 input voltage, v in (v) 0.788 0.792 0.796 0.8 0.804 0.808 0.812 reference voltage, v ref (v) reference voltage vs. input voltage 0 0.5 1.5 2.5 3.5 1 3 max. dissipation power, p d (w) 2 012345 0.5 1.5 2.5 3.5 4.5 pcb top copper area (in 2 ) max. power dissipation vs. pcb top copper area 25 35 45 55 35 75 85 t amb (c) 0 0.5 1.5 2.5 3.5 1 3 max. dissipation power, p d (w) 2 max. power dissipation vs.t amb (still air) a=5.0 in 2 a=4.5 in 2 a=4.0 in 2 a=3.5 in 2 a=3.0 in 2 a=2.5 in 2 a=2.0 in 2 a=1.5 in 2 a=1.0 in 2 a=0.5 in 2 load transient v out i out v in =3.3v,v out =2.5v,i out =0 to 2a stop short circuit current stop
LR18120 cmos ic unisonic technologies co., ltd 8 of 8 www.unisonic.com.tw qw-r502-305.a ? typical characteristics(cont.) v in start up waveform v out v in tek stop stop v pp v pp start up waveform v out v in v pp tek stop v en start up waveform v out v in v en v pp 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.
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