/2:#5,33/(#92/7$*(
5(*8/$725#:,7+#(;7(51$/
75$16,6725
$33/,&$7,21#0$18$/
5185)#6(5,(6
NO. EA-043-0006
LOW RIPPLE VOLTAGE REGULATOR
WITH EXTERNAL TRANSISTOR
5185)#6(5,(6
OUTLINE
7KH#5185)#6HULHV#DUH#YROWDJH#UHJXODWRU#,&V#ZKLFK#FRQWURO#H[WHUQDO#GULYHU#WUDQVLVWRUV#ZLWK#KLJK#ULSSOH#UHMHFWLRQ/
KLJK#DFFX0UDF\#RXWSXW#YROWDJH/#ORZ#VXSSO\#FXUUHQW#E\#&026#SURFHVV1##(DFK#RI#WKHVH#YROWDJH#UHJXODWRU#,&V#FRQVLVWV#RI#D
YROWDJH#UHIHU0HQFH#XQLW/#DQ#HUURU#DPSOLILHU/#RXWSXW#YROWDJH#VHWWLQJ#UHVLVWRU/#VKRUW#FLUFXLW#FXUUHQW#OLPLWLQJ#FLUFXLW#DQG#FKLS
HQDEOH#FLUFXLW1#7KHVH#,&V#DUH#VXLWDEOH#IRU#FRQVWUXFWLQJ#UHJXODWRUV#ZLWK#XOWUD#ORZ#GURSRXW#YROWDJH#DQG#DQ#RXWSXW#FXUUHQW
LQ#WKH#UDQJH#RI#VHYHUDO#WHQV#RI#P$#DQG#VHYHUDO#KXQGUHGV#P$1##,Q#DGGLWLRQ#WR#ORZ#VXSSO\#FXUUHQW#E\#&026#SURFHVV/#FKLS
HQDEOH#IXQFWLRQ#FDQ#EH#XVHG#WR#FRQVHUYH#EDWWHU\#OLIH#GXULQJ#VWDQGE\1
)XUWKHUPRUH/# D# VXSUHPH# ULSSOH# UHMHFWLRQ# DQG# D# WUDQVLHQW# UHVSRQVH# DUH# VXLWHG# IRU# SRUWDEOH# FRPPXQLFDWLRU# VXFK# DV
FHOO#SKRQHV/#3'$V/#ZDON\#WDONLHV1##6275608#+0LQL#0ROG,#SDFNDJH#LV#DYDLODEOH1
FEATURES
•
8OWUD#/RZ#6XSSO\#&XUUHQW
11111111111111111111111111111111111111111117<3
1#63—$
•
6WDQGE\#0RGH
1111111111111111111111111111111111111111111111111111111111111117<3
1#314—$
•
+LJK#$FFXUDF\#2XWSXW#9ROWDJH
111111111111111111111111111111111111“513(
•
+LJK#5LSSOH#5HMHFWLRQ
111111111111111111111111111111111111111111111111117<3
1#93G%2I 4N+]
•
/RZ#'URSRXW#9ROWDJH
1111111111111111111111111111111111111111111111111117<3
1#31492,
287
433P$/#GHSHQGHQW#RQ#([WHUQDO#7U1
•
/RZ#7HPSHUDWXUH#'ULIW
1111111111111111111111111111111111111111111111117<3
1#“433SSP2ƒ&
•
+LJK#/LQH#5HJXODWLRQ
1111111111111111111111111111111111111111111111111117<3
1#3138(29
•
2XWSXW#9ROWDJH111111111111111111111111111111111111111111111111111111111111116WHSZLVH# VHWWLQJ# ZLWK# D# VWHS# RI#
3149#
LQ# WKH# UDQJH# RI#
41;9#
WR
9139
•
&XUUHQW#/LPLW#IRU#H[WHUQDO#7U
111111111111111111111111111111111111117<3
1#;P$/#/LPLW#D#EDVH#FXUUHQW
APPLICATIONS
•
3RZHU#VRXUFH#IRU#EDWWHU\0SRZHUHG#HTXLSPHQW
•
7HOHFRPPXQLFDWLRQV/#&DPHUDV/#9&5V
•
3RZHU#VRXUFH#IRU#GRPHVWLF#DSSOLDQFHV
1
RN5RF
BLOCK DIAGRAM
RN5RF
××
A
4
V
DD
2
-
+
Vref
Current Limit
CE
5
Vref
Current Limit
EXT
RN5RF
××
B
4
3
V
OUT
V
DD
2
-
+
EXT
3
V
OUT
1
GND
CE
5
1
GND
SELECTION GUIDE
7KH#RXWSXW#YROWDJH/#WKH#FKLS#HQDEOH#DFWLYH#W\SH/#WKH#SDFNLQJ#W\SH#DQG#WKH#WDSLQJ#W\SH#IRU#WKH#,&V#FDQ#EH#VHOHFWHG#DW
WKH#XVHU*V#UHTXHVW1
7KH#VHOHFWLRQ#FDQ#EH#PDGH#E\#GHVLJQDWLQJ#WKH#SDUW#QXPEHU#DV#VKRZQ#EHORZ=
5185)#×××ײ××←3DUW#1XPEHU
↑ ↑↑ ↑
D EF G
Code
D
6HWWLQJ#2XWSXW#9ROWDJH#+9
287
,#=
6WHSZLVH#VHWWLQJ#ZLWK#D#VWHS#RI#3149#LQ#WKH#UDQJH#RI#41;9#WR#9139#LV#SRVVLEOH1
'HVLJQDWLRQ#RI#&KLS#HQDEOH#$FWLYH#7\SH
E
$=#´/µ#DFWLYH#W\SH
%=#´+µ#DFWLYH#W\SH
'HVLJQDWLRQ#RI#3DFNLQJ#W\SH
F
$=#7DSLQJ
&=#$QWLVWDWLF#EDJ#RQO\#IRU#VDPSOHV
G
'HVLJQDWLRQ#RI#7DSLQJ#W\SH
([1#75/#7/#+UHIHU#WR#7DSLQJ#6SHFLILFDWLRQV/#75#W\SH#LV#SUHVFULEHG#DV#D#VWDQGDUG1,
Contents
2
RN5RF
PIN CONFIGURATION
SOT-23-5
5
4
CE/CE
(mark side)
GND
V
DD
EXT
V
OUT
1
2
3
PIN DESCRIPTION
Pin No.
4
5
6
7
8
Symbol
*1'
9
''
9
287
(;7
&(#RU#&(
*URXQG#3LQ
,QSXW#3LQ
2XWSXW#3LQ
([WHUQDO#7UDQVLVWRU#'ULYH#3LQ#+&026#2XWSXW,
&KLS#(QDEOH#3LQ
Pin Description
ABSOLUTE MAXIMUM RATINGS
Symbol
9
,1
9
&(
9
(;7
,
(;7
3
'
7RSW
7VWJ
,QSXW#9ROWDJH
,QSXW#9ROWDJH#IRU#&(2&(#3LQ
(;7#2XWSXW#9ROWDJH
(;7#2XWSXW#&XUUHQW
3RZHU#'LVVLSDWLRQ
2SHUDWLQJ#7HPSHUDWXUH#5DQJH
6WRUDJH#7HPSHUDWXUH#5DQJH
Item
Rating
45
0316#WR#9
,1#
.316
45
83
483
073#WR#.;8
088#WR#.458
Unit
9
9
9
P$
P:
ƒ&
ƒ&
ABSOLUTE MAXIMUM RATINGS
$EVROXWH#0D[LPXP#UDWLQJV#DUH#WKUHVKROG#OLPLW#YDOXHV#WKDW#PXVW#QRW#EH#H[FHHGHG#HYHQ#IRU#DQ#LQVWDQW#XQGHU#DQ\#FRQ0
GLWLRQV1#0RUHRYHU/#VXFK#YDOXHV#IRU#DQ\#WZR#LWHPV#PXVW#QRW#EH#UHDFKHG#VLPXOWDQHRXVO\1#2SHUDWLRQ#DERYH#WKHVH#DEVR0
OXWH#PD[LPXP#UDWLQJV#PD\#FDXVH#GHJUDGDWLRQ#RU#SHUPDQHQW#GDPDJH#WR#WKH#GHYLFH1#7KHVH#DUH#VWUHVV#UDWLQJV#RQO\#DQG
GR#QRW#QHFHVVDULO\#LPSO\#IXQFWLRQDO#RSHUDWLRQ#EHORZ#WKHVH#OLPLWV1
3
RN5RF
ELECTRICAL CHARACTERISTICS
7RSW
58ƒ&
Symbol
9
287
,
287
,
(;7
∆9
287
2∆,
287
9
',)
,
66
,VWDQGE\
,
(;7OHDN
∆9
287
2∆9
,1
5
5
9
,1
9
(;7
∆9
287
2∆7RSW
5
38
9
&(+
9
&(/
*1)
*)
Item
2XWSXW#9ROWDJH
2XWSXW#&XUUHQW
(;7#&XUUHQW
/RDG#5HJXODWLRQ
'URSRXW#9ROWDJH
6XSSO\#&XUUHQW
6WDQGE\#&XUUHQW
(;7#/HDNDJH#&XUUHQW
/LQH#5HJXODWLRQ
5LSSOH#5HMHFWLRQ
,QSXW#9ROWDJH
(;7#2XWSXW#9ROWDJH
2XWSXW#9ROWDJH#7HPSHUDWXUH
&RHIILFLHQW
3XOO#XS#UHVLVWDQFH#IRU#&(#SLQ
&(#,QSXW#9ROWDJH#´+µ
&(#,QSXW#9ROWDJH#´/
µ
418
3
,
287
43P$
073ƒ&≤7RSW≤;8ƒ&
“433
7
9
,1
3158
,
287
83P$
9
287
.3189≤9
,1
≤439
I
4N+]/#VLQXVRLGDO#3189S0S
9
,1
09
287
4139
3
3138
93
43
43
Conditions
9
,1
0
9
287
4139
MIN.
9
287
TYP.
MAX.
9
287
Unit
9
$
,
287
83P$
9
,1
09
287
4139
9
,1
7139
(;7
5139
/#9
9
,1
09
287
4139
4P$≤,
287
≤433P$
,
287
433P$/#,
287
3P$
9
,1
09
287
4139
9
,1
43139
×31<;
413
-4
8
093
314
63
3134
314
;
×4135
48
93
315
83
413
318
3163
P$
P9
9
—$
—$
—$
(29
G%
9
9
SSP2ƒ&
0Ω
9
9
The output current depends on the performance of external PNP transistor. Use External PNP transis-
tor of a low saturation type, with an h
FE
between 100 and 300.
With respect to Test Circuit, refer to Typical Application.
4
TI技术论坛
