?2009 fairchild semiconductor corporation www.fairchildsemi.com rev. 1.0.3 features ? output current in excess of 3.0a ? output transistor safe operating area compensation ? power dissipation :25w ? internal short circuit current limiting ? internal thermal overload protection ? output voltage offered in 4% tolerance ? no external components required ? output voltage of 5,12 and 15v description this family of fixed voltage regulators are monolithic integrated circuit cap able of driving loads in excess of 3.0 a. to-220 1.input 2. gnd 3. output 1 gnd internal block diagram series pass element soa protection error amplifier thermal protection current generator reference voltage starting circuit output 3 gnd 2 input 1 lm78txx 3-terminal 3a positive voltage regulator
lm78txx 2 absolute maximum ratings note: 1. thermal resistance test board size: 76.2mm * 114.3mm * 1.6mm(1s0p) jedec standard: jesd51-3, jesd51-7 2. assume no ambient airflow. electrical characteristics(lm78t05) (v i = 10v, i o = 3.0 a, 0 c t j +125 c, po p max (note3), unless otherwise specified. ) note: 3. although power dissipation is internally limited, specifications apply only for p o pmax, pmax = 25w 4. load and line regulation are specified at constant junction temperatur e. change in vo due heating effects must be taken into account separately. pulse te sting with low duty is used. parameter symbol value unit input voltage (for v o = 5v to 12v) (for v o = 15v) v i 35 40 v v power dissipation pd internally limited thermal resistance, junction to air (note1, 2) ta = +25 c r ja 65 c/w thermal resistance, junction to case (note1) tc = +25 c r jc 2.5 c/w operating junction temperature range t j 0 ~ +125 c storage temperature range t stg -65 ~ +150 c parameter symbol conditions min. typ. max. unit output voltage vo 5ma io 3.0a , t j = +25 c 7.3v vi 20v, 5ma io 2.0a 4.8 4.75 5.0 5.0 5.2 5.25 v line regulation (note4) v o 7.2v vi 35v , io=5ma, t j =+25 c 7.2v vi 35v , io=1.0a, t j = +25 c 7.5v vi 20v, io =2.0a, t j = +25 c 8.0v vi 12v, io =3.0a, t j = +25 c -3.025mv load regulation (note4) v o 5ma io 3.0a , t j = +25 c 5ma io 3.0a - 10 15 30 80 mv mv thermal regulation reg t pulse =10ms, p = 20w t a = +25 c - 0.002 0.03 %vo/w quiescent current i q 5ma io 3.0a , t j = +25 c 5ma io 3.0a - 3.5 4.0 5.0 6.0 ma ma quiescent cu rrent change i q 7.2v vi 35v, io = 5ma t j = +25 c ; 7.5v vi 20v, io =2.0a ; 5ma io 3.0a, t j = +25 c -0.10.8ma ripple rejection rr f = 120hz, 8v v i 18v, i o = 2.0a t j = +25 c -75- db dropout voltage v d io = 3a ,t j = +25 c-2.22.5v output noise voltage v n t a = +25 c, 10hz f 100khz - 10 - v/vo peak output current i pk t a = +25 c-5.0-a output resistance ro f = 1.0khz - 2.0 - m short circuit current limit isc vi = 35v, t j =+25 c-1.52.5a average temperature coefficient of output voltage v o / t io = 5.0ma - 0.2 - mv/ c
lm78txx 3 electrical characteristics(lm78t12) (continued) (v i = 19v, i o = 3.0 a, 0 c t j +125 c, po p max (note1), unless otherwise specified. ) note: 1. although power dissipation is internally limited, specifications apply only for p o pmax, pmax = 25w 2. load and line regulation are specified at constant junction temperat ure. change in vo due heating effects must be taken into account separately. pulse test ing with low duty is used. ( p max = 25w) parameter symbol conditions min. typ. max. unit output voltage vo 5ma io 3.0a , t j =+25 c 14.5v vi 27v, 5ma io 2.0a 11.5 11.4 12 12 12.5 12.8 v line regulation (note2) v o 14.5v vi 35v, io=5ma, t j =+25 c 14.5v vi 35v, io=1.0a, t j =+25 c 14.9v vi 28v, io =2.0a, t j =+25 c 16v vi 22v, io =3.0a, t j =+25 c -6.045mv load regulation (note2) v o 5ma io 3.0a, t j =+25 c 5ma io 3.0a - 10 15 30 80 mv mv thermal regulation reg t pulse =10ms, p = 20w t a = +25 c - 0.002 0.03 %vo/w quiescent current i q 5ma io 3.0a, t j =+25 c 5ma io 3.0a - 3.5 4.0 5.0 6.0 ma ma quiescent cu rrent change i q 14.5v vi 35v, io = 5ma t j =+25 c ; 14.9v vi 27v, io =2.0a ; 5ma io 3.0a, t j =+25 c -0.10.8ma ripple rejection rr f = 120hz, 15v v i 25v, io = 2.0a t j =+25 c -67- db dropout voltage v d io = 3a,t j =+25 c-2.22.5v output noise voltage v n t a =+25 c, 10hz f 100khz - 10 - v/vo peak output current i pk t a =+25 c-5.0-a output resistance ro f = 1.0khz - 2.0 - m short circuit current limit isc vi = 35v, t j =+25 c-1.52.5a average temperature coefficient of output voltage v o / t io = 5.0ma - 0.5 - mv/ c
lm78txx 4 electrical characteristics(lm78t15) (continued) (v i = 23v, i o = 3.0 a, 0 c t j +125 c, po p max (note1), unless otherwise specified. ) note: 1. although power dissipation is internally limited, specifications apply only for p o pmax, pmax = 25w 2. load and line regulation are specified at constant junction temperature. change in vo due heating effects must be taken into account separately. pulse test ing with low duty is used. ( p max = 25w) parameter symbol conditions min. typ. max. unit output voltage vo 5ma io 3.0a, t j =+25 c 17.5v vi 30v, 5ma io 2.0a 14.4 14.25 15 15 15.6 15.75 v line regulation (note2) v o 17.6v vi 40v, io=5ma, t j =+25 c 17.6v vi 40v, io=1.0a, t j =+25 c 18v vi 30v, io =2.0a, t j =+25 c 20v vi 26v, io =3.0a, t j =+25 c -7.555mv load regulation (note2) v o 5ma io 3.0a, t j =+25 c 5ma io 3.0a - 10 15 30 80 mv mv thermal regulation reg t pulse =10ms, p = 20w t a = +25 c - 0.002 0.03 %vo/w quiescent current i q 5ma io 3.0a, t j =+25 c 5ma io 3.0a - 3.5 4.0 5.0 6.0 ma ma quiescent cu rrent change i q 17.6v vi 40v, io = 5ma t j =+25 c ; 18v vi 30v, io =2.0a ; 5ma io 3.0a, t j =+25 c -0.10.8ma ripple rejection rr f = 120hz, 18.5v v i 28.5v, io = 2.0a t j =+25 c -65- db dropout voltage v d io = 3a ,t j = +25 c-2.22.5v output noise voltage v n t a = +25 c, 10hz f 100khz - 10 - v/vo peak output current i pk t a = +25 c-5.0-a output resistance ro f = 1.0khz - 2.0 - m short circuit current limit isc vi = 40v, t j = +25 c-1.02.0a average temperature coefficient of output voltage v o / t io = 5.0ma - 0.5 - mv/ c
lm78txx 5 typical application note: 1. to specify an output voltage, substitute voltage value for ?xx?. 2. bypass capacitors are recommend for optimum stability and tr ansient response and should be located as close as possible to the regulator ka78txx input output 3 2 1 0.33 f 0. 1 f lm78txx
lm78txx 6 mechanical dimensions package dimensions in millimeters to-220 [ single gauge ]
lm78txx 7 ordering information product number package operating temperature lm78t05ct to-220 0 ~ +125 c LM78T12CT lm78t15ct
lm78txx 7/6/09 0.0m 001 stock#ds903490 ? 2009 fairchild semiconductor corporation life support policy fairchild?s products are not authorized for use as critical components in life support devices or systems without the express written approval of the president of fairchild semiconductor corporation. as used herein: 1. life support devices or systems are devices or systems which, (a) are intended for surgical implant into the body, or (b) support or sustain lif e, and (c) whose failure to perform when properly used in accordance with instructions for use provided in the labeling, can be reasonably expected to result in a significant injury of the user. 2. a critical component in an y component of a life support device or system whose fa ilure to perform can be reasonably expected to cause the failure of the life support device or system, or to affect its safety or effectiveness. www.fairchildsemi.com disclaimer fairchild semiconductor reserves the right to make changes with out further notice to any products herein to improve re liability, function or design. fairchild does not assume any liability arising out of the applic ation or use of any product or circuit described herein; neither does it convey any license under its pat ent rights, nor the rights of others.
|
