L4948 quad voltage regulator with inhibit and reset 4 outputs: 10v (300ma); 8v (400ma); 5v (600ma); 5v (100ma) all four outputs are low drop 5v (100ma) st-by output voltage early warning output for supply undervoltage (lvw) thermal shutdown and current limitation (foldback) reverse battery and load dump protection inhibit (on/off) and reset functions description the L4948 is a quad output low drop voltage regulator. all four outputs are low drop: 10v at 300ma (v o1 ), 8v at 400ma (v o2 ), 5v at 600ma (v o3 ) and a 5v st-by line at 100ma (v o4 ). the ic includes a monitoring circuit to warn if a low voltage or no voltage condition is occurring. v o1,2,3 are off during st-by mode. the stcap pin allows the battery voltage to de- cay slowly giving the m p time to store data. this ic is designed for supplying microcomputer con- trolled systems specially in automotive applica- tions. june 2000 ? block diagram multiwatt 11 ordering number: L4948 multipower bcd technology 1/9
operating condition symbol parameter value unit v s supply voltage -15 to 27 v i l load current i o1 i o2 i o3 i o4 300 400 600 100 ma ma ma ma thermal data symbol parameter value unit r th j-case thermal resistance junction-case max 2 c/w pin connection absolute maximum ratings symbol parameter value unit v s supply voltage -35 to 60 v v i input voltage (on/off) 0 to 12 v v o output voltage (lvw, reset) 0 to 12 v t stg storage temperature range -65 to 150 c t j junction temperature range max 150 c load dump (5ms rise, 115ms decay) 60 v application circuit L4948 2/9
electrical characteristics (v s = 10.5 to 16v; i o1 = 6ma, i o2 = 8ma, i o3 = 4ma; i o4 = 0.4ma; c o =10 m f max; t amb = -40 to 85 c, unless otherwise specified.) symbol parameter test condition min. typ. max. unit v o1 output voltage i o1 = 300ma; t amb =25 c; 11v < v s < 16v all temps 9.7 9.5 10 10 10.3 10.5 v v d v o1 load regulation i o1 = 6 to 300ma 150 mv i q quiescent current ( d i s )v s = 14v; i o1 = 6ma; v s =14v ; i o1 = 300ma; 10 30 ma ma v s -v o1 dropout voltage i o1 = 300ma t amb =25 c; all temps 400 600 mv mv i l current limit (foldback) note1 v o1 = 0v 360 800 ma v o1 max bat.trans. r o = 100 w ramp v s from 14 to 60v in 3-5ms 11 v hold v s at 60v for 10ms ramp v s from60 to 14v in 3-5ms; t amb =25 c; all temps 9.7 9.5 10 10 2 10.3 10.5 v v v v o1 rev. voltage trans. v s = -35v; t 1ms; r o = 100 w check v o1 ,t amb =25 c; all temps 9.7 9.5 10 10 10.3 10.5 v v v o1 rev. voltage . v s = -15v; r o = 100 w -0.4 1 v ripple rejection f o =1khz;1v pp ac ; v s =14v i o1 = 180ma; i o2 = 200ma ; i o3 = 400ma; i o4 = 40ma; 50 db f o =10khz;1v pp ac ; v s =14v i o1 = 180ma; i o2 = 200ma ; i o3 = 400ma; i o4 = 40ma; 50 db d v o1 line regulation d v o1 across v s range v s = 11v to 26v 50 mv output noise check output for ac noise using a 100khz lp filter check output for ac noise using an a weighted filter (20- 20khz) 400 200 m v m v v o2 output voltage i o2 = 400ma; t amb =25 c; all temps 7.75 7.60 8 8 8.25 8.40 v v d v o2 load regulation i o2 = 8 to 400ma 150 mv d i q quiescent current ( d i s )v s = 14v; i o2 = 8ma; v s = 14v; i o2 = 400ma; 10 35 ma ma v s -v o2 dropout voltage i o2 = 400ma set v s =v o2 +1v; t amb =25 c; set v s =v o2 +1.5v;all temps 400 600 mv mv i l current limit (foldback) note1 v o2 = 0v 480 960 ma v o2 max bat.trans. r o = 100 w ramp v s from 14 to 60v in 3-5ms 9 v hold v s at 60v for 10ms ramp v s from60 to 14v in 3-5ms; t amb =25 c; all temps 7.75 7.60 8 8 2 8.25 8.40 v v v L4948 3/9
electrical characteristics (continued) symbol parameter test condition min. typ. max. unit v o2 rev. voltage trans. v s = -35v; r o = 100 w t 1ms check v o2 , standard t amb =25 c; all temps 7.75 7.60 8 8 8.25 8.40 v v v o2 rev. voltage . v s = -15v; t = 30s; r o = 100 w -0.4 1 v ripple rejection f o =1khz;1v pp ac ; v s =14v i o1 = 180ma; i o2 = 200ma ; i o3 = 400ma; i o4 = 40ma; 50 db f o =10khz;1v pp ac ; v s =14v i o1 = 180ma; i o2 = 200ma ; i o3 = 400ma; i o4 = 40ma; 50 db d v o2 line regulation d v o2 across v s range v s = 10.5v to 26v 40 mv v o3 output voltage i o3 = 600ma; t amb =25 c; all temps 4.85 4.75 5 5 5.15 5.25 v v d v o3 line regulation v s = 7v to 26v 40 mv d v o3 load regulation i o3 = 4 to 600ma 100 mv d i q quiescent current ( d i s )v s = 14v; i o3 = 4ma; v s = 14v; i o3 = 600ma; 8 40 ma ma v s -v o3 dropout voltage i o3 = 600ma set v s =v o3 +1v; t amb =25 c; set v s =v o3 +1.5v;all 400 600 mv mv i l current limit (foldback) note 1 v o3 = 0v 720 1440 ma v o3 max bat.trans. r o = 100 w ramp v s from 14 to 60v in 3-5ms 6 v hold v s at 60v for 10ms ramp v s from60 to 14v in 3-5ms; t amb =25 c; all temps 4.85 4.75 5 5 2 5.15 5.25 v v v v o3 rev. voltage trans. v s = -35v; t < 1ms; r o = 100 w check v o3 , standard t amb =25 c; all temps 4.85 4.75 5 5 5.15 5.25 v v v o3 rev. voltage . v s = -15v; r o = 100 w -0.4 1 v ripple rejection f o =1khz;1v pp ac ; v s =14v i o1 = 180ma; i o2 = 200ma ; i o3 = 400ma; i o4 = 40ma; 50 db f o = 10khz; 1v pp ac ; v s =14v 50 db output noise check output for ac noise using a 100khz lp filter check output for ac noise using an a weighted filter (20- 20khz) 400 200 m v m v v o4 output voltage i o4 = 100ma; t amb =25 c; all temps 4.85 4.75 5 5 5.15 5.25 v v d v o4 line regulation v s = 7v to 26v 40 mv d v o4 load regulation i o4 = 0.4 to 100ma 80 mv d i q quiescent current v s = 14v; i o4 = 2ma; v s = 14v; i o4 = 100ma; 450 20 m a ma v s -v o4 dropout voltage i o4 = 100ma set v s =v o4 +0.5v; t amb =25 c; set v s =v o4 +0.8v;all temps 400 600 mv mv i l current limit (foldback) note 1 v o4 = 0v 150 300 ma L4948 4/9
electrical characteristics (continued) symbol parameter test condition min. typ. max. unit v o4 max bat.trans. r o = 100 0w ramp v s from 14 to 60v in 3-5ms 6 v hold v s at 60v for 10ms ramp v s from60 to 14v in 3-5ms; t amb =25 c; all temps 4.85 4.75 5 5 6 5.15 5.25 v v v v o4 rev. voltage trans. v s = -35v; t < 1ms; r o = 100 0w check v o4 , standard t amb =25 c; all temps 4.85 4.75 5 5 5.15 5.25 v v v o4 rev. voltage . v s = -15v; r o = 1000 w -0.4 1 v ripple rejection f o =1khz;1v pp ac ; v s =14v i o1 = 180ma; i o2 = 200ma ; i o3 = 400ma; i o4 = 40ma; 50 db f o = 10khz; 1v pp ac ; v s =14v i o1 = 180ma; i o2 = 200ma ; i o3 = 400ma; i o4 = 40ma; 50 db output noise check output for ac noise using a 100khz lp filter check output for ac noise using an a weighted filter (20- 20khz) 400 200 m v m v on/off input current v s = 14v; v ih = >2v; v s = 14v; v il = <0.8v; -10 1 m a m a v i on/off input threshold v s = 14v v il v s = 14v v ih 0 2 0.8 12 v v v r reset output voltage set v s so that v o4 < 4.5v; r o =200k w to v 04 ;v il = o0o 0 0.75 v v s so that v o4 -0.15v; r o =200k w to v 04 ;v ih =o1o 2.75 5 v lvw and reset fall time set measured from 90% to 10% 150 m s lvw and reset rise time measured from 90% to 100% 300 m s lvw output threshold ramp v s down until lvw switches fromo1o to a o0o 7.0 8.2 v lvw output voltage stcap <6.5v;r o =200k w to v o4 ;v il = o0o 0 0.75 v stcap >7.5v;r o =200k w to v o4 ;v ih =o1o 2.75 50 v reset output stability v s is set such that 1 < v 04 < 4v; i out4 = 2ma; v on/off =0 meas reset variation 50 mv i q st-by quiescent current ( d i s )v on/off =0v ; i o4 = 100ma; v s = 14v; i o1,2,3 = 0ma 20 ma v on/off =0v ; i o4 = 2ma; v bat = 14v; i o1,2,3 = 0ma 500 m a maximum quiescent current ( d i s ) v s = 14v; i o1 = 300ma; i o2 = 400ma ; i o3 = 600ma; i o4 = 100ma; v o =5v 110 ma stcap output voltage v s =24v; v s = 60v. 1ms 15 17 18 v v note 1: the L4948 has ofoldbacko on its outputs during current limiting. as the output loading is increasing the current supplied by the L4948 increases until a threshold is reached. when the current limiting threshold is reached, the L4948 output current will start to accrease as the loading is continuoing to increase. the point where the output current stort to decrease is the maximum output current. L4948 5/9
functional description the L4948 includes a monitoring circuit to warn the microprocessor if a low voltage or no voltage condition is occurring. between 6.5v and 7.5v on the stcap pin, the lvw output will go low. this tells the microprocessor to stop executing code and save vital information. the reset output will go low when v 04 drops 0.15v below it's typical reading. a reset will occur between a minimum of 4.5 and a maximum of 5v on v 04 . when the v 04 drops between 4.5 and 5v the reset output goes low. it is very important that the reset out- put doesn't go above 0.75v until the v 04 output has gone back above 4.75v (typical). the micro- processor looks for a rising edge. so, any spike will tell the microprocessor to start operating. once the stcap line passes 7v (typical), the lvw output will also return to high state. timing diagram graphs of the output curves for v o1,2,3 and 4 5.0 5.0 7.8 L4948 6/9
the stcap pin acts like a delay circuit. due to the large capacitor (470 m f), the stcap pin allows the battery voltage to decay slowly giving the mi- croprocessor time to store data. also, during short low voltage or negative voltage conditions, the stcap pin protects the 5v st-by output from dropping below the reset and lvw trip points the four outputs are expected to follow the bat- tery voltage down to 7v. at 7v typical the lvw tells the microprocessor to stop operation and save operating data below 7v the outputs are ex- pected to stay alive and ready for a return of bat- tery. the L4948 has a st-by mode to keep the micro- processor and memories allive during an ignition off conditions. the on/off input pin in controlled by the microprocessor. an high on the on/off pin places the part in normal mode. a low on the on/off pin places the part in st-by mode.v 01 , v 02 ,v 03 will be off during st-by mode. graphs of the output curves for v o1,2,3 and 4 (cont.) notes and information the following information is for clarification, not for specification definition. please use the information in this way. L4948 7/9
multiwatt11 v dim. mm inch min. typ. max. min. typ. max. a 5 0.197 b 2.65 0.104 c 1.6 0.063 d 1 0.039 e 0.49 0.55 0.019 0.022 f 0.88 0.95 0.035 0.037 g 1.45 1.7 1.95 0.057 0.067 0.077 g1 16.75 17 17.25 0.659 0.669 0.679 h1 19.6 0.772 h2 20.2 0.795 l 21.9 22.2 22.5 0.862 0.874 0.886 l1 21.7 22.1 22.5 0.854 0.87 0.886 l2 17.4 18.1 0.685 0.713 l3 17.25 17.5 17.75 0.679 0.689 0.699 l4 10.3 10.7 10.9 0.406 0.421 0.429 l7 2.65 2.9 0.104 0.114 m 4.25 4.55 4.85 0.167 0.179 0.191 m1 4.73 5.08 5.43 0.186 0.200 0.214 s 1.9 2.6 0.075 0.102 s1 1.9 2.6 0.075 0.102 dia1 3.65 3.85 0.144 0.152 outline and mechanical data L4948 8/9
information furnished is believed to be accurate and reliable. however, stmicroelectronics assumes no responsibility for the consequences of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. no license is granted by implication or otherwise under any patent or patent rights of stmicroelectronics. specification mentioned in this publication are subject to change without notice. this publication supersedes and replaces all information previously supplied. stmicroelectronics products are not authorized for use as critical components in life support devices or systems without express written approval of stmicroelectronics. the st logo is a registered trademark of stmicroelectronics ? 2000 stmicroelectronics printed in italy all rights reserved stmicroelectronics group of companies australia - brazil - china - finland - france - germany - hong kong - india - italy - japan - malaysia - malta - morocco - singapore - spain - sweden - switzerland - united kingdom - u.s.a. http://www.st.com L4948 9/9
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