ace 1117 1 a positive voltage re gulator s ver 1. 4 1 d escription ace1117 series of high performance low dropout voltage regulators are designed for applications that require efficient conversion and fast transient response. in addition, ace1117 is designed to be stable under conditions where cin and cout ar e not present. however, it is recommended to include cin and cout in the system design as this will speed up the transient response and increase the psrr rating. features low dropout performance. low quiescent current: 3ma (typ.) guaranteed 1a output current. wide input supply voltage r ang e. stable operation without cin and cout. over - temperature and over - current protection fixed or adjustable output vo lt age. rugged 2kv esd withstand capability. application active scsi terminators high efficiency linear regulators 5v to 3.3v linear regulators motherboard clock suppl ies absolute maximum ratings parameter symbol max unit input voltage v in 9 v j unction temperature t j - 40 to 130 o c thermal resistance junction to ambient ja 60 o c /w storage temperature t s - 40 to 150 o c packaging type sot - 223 to - 252 1 2 3 1 2 3 sot - 223 / to - 252 description 1 adj/ gnd 2 vout 3 vin
ace 1117 1 a positive voltage re gulator s ver 1. 4 2 ordering information ace 1117 xx xx + h electrical characteristics v in.max Q 8v, v in.max - v out =1.5v, i out =10ma, c in =10uf, c out =22uf, t a =25 , unless otherwise specified. parameter symbol test conditions min typ m um unit output voltage (1) v o ace1117 - 15 ace1117 - 18 ace1117 - 25 ace1117 - 33 ace1117 - 50 1.470 1.764 2.450 3.234 4.900 1.5 1. 8 2.5 3.3 5.0 1.530 1.836 2.550 3.366 5.100 v reference voltage (1) (adj. voltage version) v ref (v in - v out )=1.5v i out =10ma ( - 2%) 1.250 (+2%) v line regulation (1) v sr v out +1.5v ace 1117 1 a positive voltage re gulator s ver 1. 4 3 thermal protection otp 175 rms output noise v n t a =25 , 10hz Q f Q 100khz 0.003 %v o ripple rejection ratio r a f=120hz, cout=22uf (tantalum), (v in - v out )=3v, i out =10ma 55 db note1 : low duty c ycle pulse testing with which t j remains unchanged. 2: the i q of ace1117 - 1.5 is 1.2ma (typ.) 3: the dropout voltage is the input/output differential at which the circuit ceases to regulate against further reduction in input typical application a djus table voltage regulator vin >=3.0v ace1117 vout =1.5v vin vout adj r1 cin 124ohm cout 10uf 22uf r2 24.9ohm v out =v ref * (1+r2/r1)+i adj * r2 ace1117 - 3.3 fixed voltage regulator application hints the typical linear regulato r would require external capacitors to ensure stability. however, ace 11 1 7 is designed in such a way that these external capacitor can be omitted if the pcb layout is tight and system noise is not very high. for better transient and psrr performance, the in put and output capacitors are still recommended.
ace 1117 1 a positive voltage re gulator s ver 1. 4 4 input capacitor an input capacitor of 10f is recommended. ce ramic or tantalum can be used. the value can be increased without upper limit. output capacitor an output capacitor of 22uf is recommended for better transient and psrr performance. it should be placed no more than 1 cm away from the v out pin, and connected directly between v out and gnd pins. the value may be increased without upper limit. thermal considerations it is important that the thermal limit of the package is not exceeded. the ace1 117 has buil t - in thermal protection. when the thermal limit is exceeded, the ic will enter protection, and vout will be pulled to ground. the power dissipation for a given application can be calculated as following: the power dissipation (p d ) is p d = i out * [v in C v out ] the thermal limit of the package is then limited to p d(max) = [t j C t a ]/ ja whe re t j is the junction temperature, t a is the ambient temperature, and ja is around 180c/w for ace1 117 . ace1 117 is designed to enter thermal protection at 175c. f or example, if ta is 25c then the maximum pd is limited to about 0.83w. in other words, if i out(max) = 500ma, then [v in C v out ] can not exceed 1.66v. (ref. so t - 223 without heat sink.) typical performance characteristic reference voltage vs junction t emperature output voltage vs junction temperature junction temperature ( ) junction temperature ( )
ace 1117 1 a positive voltage re gulator s ver 1. 4 5 dropout voltage vs output current psrr vs frequency output current (ma ) frequency (hz) liine transients load transients short transient response
ace 1117 1 a positive voltage re gulator s ver 1. 4 6 packing information sot - 223
ace 1117 1 a positive voltage re gulator s ver 1. 4 7 packing information to - 252
ace 1117 1 a positive voltage re gulator s ver 1. 4 8 notes ace does not ass ume any responsibility for use as critical components in life support devices or systems without the express written approval of the president and general counsel of ace electronics co., ltd. as sued herein: 1. life support devices or systems are devices or s ystems which, (a) are intended for surgical implant into the body, or (b) support or sustain life, and shoes failure to perform when properly used in accordance with instructions for use provided in the labeling, can be reasonably expected to result in a s ignificant injury to the user. 2. a critical component is any component of a life support device or system whose failure to perform can be reasonably expected to cause the failure of the life support device or system, or to affect its safety or effectiveness. ace technology co., ltd. http://www.ace - ele.com/
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