ETC R1221N40XF-TR

6WHS0GRZQ#'&2'&#&RQYHUWHU
&RQWUROOHU#ZLWK#9ROWDJH#'HWHFWRU
545541#6(5,(6
$33/,&$7,21#0$18$/
NO. EA-066-0006
Step-down DC/DC Converter Controller
with Voltage Detector
545541#6(5,(6
OUTLINE
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VXSSO\#FXUUHQW#E\#&026#SURFHVV1
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FDQ#EH#GHVLJQDWHG#E\#XVHUV*#UHTXHVW1
FEATURES
• :LGH#5DQJH#RI#,QSXW#9ROWDJH111111111111111111111111111111111111111111111 5169#WR#46159
• %XLOW0LQ#6RIW0VWDUW#)XQFWLRQ#DQG#WZR#FKRLFHV#RI#3URWHFWLRQ#)XQFWLRQ#+/DWFK0W\SH#RU#5HVHW0W\SH,
• 7ZR#FKRLFHV#RI#2VFLOODWRU#)UHTXHQF\11111111111111111111111111111111 633N+]/#833N+]
• +LJK#(IILFLHQF\ 111111111111111111111111111111111111111111111111111111111111111111 7<31#<3(
• 6WDQGE\#&XUUHQW 1111111111111111111111111111111111111111111111111111111111111111 7<31#3µ$
• 6HWWLQJ#2XWSXW#9ROWDJH 111111111111111111111111111111111111111111111111111111 6WHSZLVH#VHWWLQJ#ZLWK#D#VWHS#RI#3149#LQ#WKH#UDQJH#RI#4189
WR#8139
• +LJK#$FFXUDF\#2XWSXW#9ROWDJH 11111111111111111111111111111111111111111 ±513(
• 6HWWLQJ#'HWHFWRU#7KUHVKROG#9ROWDJH111111111111111111111111111111111 6WHSZLVH#VHWWLQJ#ZLWK#D#VWHS#RI#3149#LQ#WKH#UDQJH#RI#4159
WR#7189
• +LJK#$FFXUDF\#'HWHFWRU#7KUHVKROG#9ROWDJH 11111111111111111111 ±513(
• /RZ#7HPSHUDWXUH0'ULIW#&RHIILFLHQW#RI#2XWSXW#9ROWDJH1111 7<31#“433SSP2ƒ&
1
R1221N
APPLICATIONS
• 3RZHU#VRXUFH#IRU#KDQG0KHOG#FRPPXQLFDWLRQ#HTXLSPHQW/#FDPHUDV/#YLGHR#LQVWUXPHQWV#VXFK#DV#9&5V/#FDPFRUGHUV1
• 3RZHU#VRXUFH#IRU#EDWWHU\0SRZHUHG#HTXLSPHQW1
• 3RZHU#VRXUFH#IRU#KRXVHKROG#HOHFWULFDO#DSSOLDQFHV1
BLOCK DIAGRAM
OSC
VIN
VOUT
EXT
Vref
PWM/VFM
CONTROL
Protection
Soft Start
Chip Enable
Vref
VDOUT
GND
2
CE
R1221N
SELECTION GUIDE
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WKH#WDSLQJ#W\SH#IRU#WKH#,&V#FDQ#EH#VHOHFWHG#DW#WKH#XVHU*V#UHTXHVW1
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545541;;;;075
↑ ↑↑
D EF
Code
D
Contents
6HWWLQJ#2XWSXW#9ROWDJH#+9287,=
6WHSZLVH#VHWWLQJ#ZLWK#D#VWHS#RI#3149#LQ#WKH#UDQJH#RI#4189#WR#8139#LV#SRVVLEOH1
6HWWLQJ#'HWHFWRU#7KUHVKROG#+09'(7,
E
6WHSZLVH#VHWWLQJ#ZLWK#D#VWHS#RI#3149#LQ#WKH#UDQJH#RI#4159#WR#7189#LV#SRVVLEOH1
$#=#6139
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%#=#833N+]/#ZLWK#D#3:029)0#DOWHUQDWLYH#FLUFXLW/#/DWFK0W\SH#SURWHFWLRQ
&#=#633N+]/#ZLWKRXW#D#3:029)0#DOWHUQDWLYH#FLUFXLW/#/DWFK0W\SH#SURWHFWLRQ
F
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(#=#633N+]/#ZLWK#D#3:029)0#DOWHUQDWLYH#FLUFXLW/#5HVHW0W\SH#SURWHFWLRQ
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*#=#633N+]/#ZLWKRXW#D#3:029)0#DOWHUQDWLYH#FLUFXLW/#5HVHW0W\SH#SURWHFWLRQ
+#=#833N+]/#ZLWKRXW#D#3:029)0#DOWHUQDWLYH#FLUFXLW/#5HVHW0W\SH#SURWHFWLRQ
PIN CONFIGURATION
SOT-23-6W
6
5
4
VOUT GND CE
(mark side)
EXT VDOUT VIN
1
2
3
3
R1221N
PIN DESCRIPTION
Pin No.
Symbol
Description
4
(;7
5
9'287
6
9,1
3RZHU#6XSSO\#3LQ
7
&(
&KLS#(QDEOH#3LQ
8
*1'
*URXQG#3LQ
9
9287
3LQ#IRU#0RQLWRULQJ#2XWSXW#9ROWDJH
([WHUQDO#7UDQVLVWRU#'ULYH#3LQ#+2XWSXW#7\SH#>#&026,
9ROWDJH#'HWHFWRU#2XWSXW#3LQ#+2XWSXW#7\SH#>#1FK#2SHQ#'UDLQ,
ABSOLUTE MAXIMUM RATING
Symbol
Rating
Unit
48
9
9,1
9,1#6XSSO\#9ROWDJH
9(;7
(;7#3LQ#2XWSXW#9ROWDJH
0316∼9,1.316
9
9&(
&(#3LQ#,QSXW#9ROWDJH
0316∼9,1.316
9
0316∼48
9
0316∼9,1.316
9
9'287
4
Item
9'287#3LQ#2XWSXW#9ROWDJH
9287
9287#3LQ#,QSXW#9ROWDJH
,(;7
(;7#3LQ#,QGXFWRU#'ULYH#2XWSXW#&XUUHQW
“58
P$
3'
3RZHU#'LVVLSDWLRQ
583
P:
7RSW
2SHUDWLQJ#7HPSHUDWXUH#5DQJH
073∼.;8
ƒ&
7VWJ
6WRUDJH#7HPSHUDWXUH#5DQJH
088∼.458
ƒ&
R1221N
ELECTRICAL CHARACTERISTICS
• R1221N***A (C,E,G) Output Voltage : Vo, Detector Threshold : VD
Symbol
9,1
Item
2SHUDWLQJ#,QSXW#9ROWDJH
9287
6WHS0GRZQ#2XWSXW#9ROWDJH
∆92872
6WHS0GRZQ#2XWSXW#9ROWDJH
∆7
7HPSHUDWXUH#&RHIILFLHQW
IRVF
2VFLOODWRU#)UHTXHQF\
∆IRVF2
Conditions
)UHTXHQF\#7HPSHUDWXUH
9,1 9&( 9R.4159/#,287 043P$
9,1 9&( 9R.4159/#,287 0433P$
6XSSO\#&XUUHQW4
,VWE
6WDQGE\#&XUUHQW
,(;7+
(;7#´+µ#2XWSXW#&XUUHQW
,(;7/
(;7#´/µ#2XWSXW#&XUUHQW
,&(+
&(#´+µ#,QSXW#&XUUHQW
,&(/
&(#´/µ#,QSXW#&XUUHQW
9,1 46159/#9&( 39/#9287 46159
9&(+
&(#´+µ#,QSXW#9ROWDJH
9,1 ;9/#9&( 39→4189
9&(/
&(#´/µ#,QSXW#9ROWDJH
9,1 ;9/#9&( 4189→39
7SURW
,9'/.
,9'/
9,1 ;9/#9(;7 :1<9/#9287 ;9/
9&( ;9
9,1 ;9/#9(;7 3149/#9287 39/
9&( 39
4615
9R
633
9R×
4135
0318
9
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SSP2
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693
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IXQFWLRQ
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9,1 9R.4159/#9&( 9R.4159→39
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318
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043
09
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'
P$
(
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9
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9
53
318
3
415
31;
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(
58
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8
43
49
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PV
4
6
8
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PV
3
318
,
—$
,
P$
9,1 9287 9&( 9'287 ;9
9,1 9287 5169/#9&( 39/
N+]
(2ƒ&
433
9,1 9R.4159/#9&( 39→9R.4159
9
493
31;
316
Unit
433
3
9287 46159
'HOD\#7LPH#E\#6RIW06WDUW
9'287#´/µ#2XWSXW#&XUUHQW
43
9,1 46159/#9&( 46159/
$SSOLHG#WR#%#DQG#)#YHUVLRQV#RQO\
&XUUHQW
MAX. Note*
“316
9,1 46159/#9&( 39/#9287 39
9)0#'XW\#&\FOH
9'287#2XWSXW#/HDNDJH
573
9287 46159
&\FOH
FLUFXLW
TYP.
“433
9,1 46159/#9&( 46159/
2VFLOODWRU#0D[LPXP#'XW\
'HOD\#7LPH#IRU#SURWHFWLRQ
31<;
073ƒ&≤7RSW≤;8ƒ&
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7VWDUW
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073ƒ&≤7RSW≤;8ƒ&
&RHIILFLHQW
9)0GW\
MIN.
516
∆7
0D[GW\
+7RSW 58ƒ&,
318
4
5
R1221N
Symbol
09'(7
W9'(7
9+<6
∆09'(72
∆7
Item
'HWHFWRU#7KUHVKROG
2XWSXW#'HOD\#7LPH#IRU
5HOHDVHG#9ROWDJH
MIN.
9,1 99/#9&( 99/
9'×
9287 9'×4159→39
31<;
TYP.
9'
MAX. Note*
9'×
4135
9287 39→9'×4159
5
8
43
9'×
9'×
9'×
WHUHVLV
9287 39→9'×4159
3134
3136
3138
SHUDWXUH#&RHIILFLHQW
-
9
-
PV
-
P9
$W#;3(#RI#ULVLQJ
9,1 99/#9&( 99/
'HWHFWRU#7KUHVKROG#7HP0
Unit
9,1 99/#9&( 99/
'HWHFWRU#7KUHVKROG#+\V0
1RWH=#5HIHU#WR#7HVW#&LUFXLWV
6
Conditions
073ƒ&≤7RSW≤;8ƒ&
“433
SSP2
ƒ&
R1221N
• R1221N***B (D,F,H) Output Voltage : Vo, Detector Threshold : VD
Symbol
9,1
Item
2SHUDWLQJ#,QSXW#9ROWDJH
9287
6WHS0GRZQ#2XWSXW#9ROWDJH
∆92872
6WHS0GRZQ#2XWSXW#9ROWDJH
∆7
7HPSHUDWXUH#&RHIILFLHQW
IRVF
2VFLOODWRU#)UHTXHQF\
∆IRVF2∆7
Conditions
)UHTXHQF\#7HPSHUDWXUH
&RHIILFLHQW
9,1 9&( 9R.4159/#,287 043P$
9,1 9&( 9R.4159/#,287 0433P$
,(;7+
(;7#´+µ#2XWSXW#&XUUHQW
,(;7/
(;7#´/µ#2XWSXW#&XUUHQW
,&(+
&(#´+µ#,QSXW#&XUUHQW
,&(/
&(#´/µ#,QSXW#&XUUHQW
9,1 46159/#9&( 39/#9287 46159
9&(+
&(#´+µ#,QSXW#9ROWDJH
9,1 ;9/#9&( 39→4189
9&(/
&(#´/µ#,QSXW#9ROWDJH
9,1 ;9/#9&( 4189→39
,9'/.
,9'/
09'(7
9,1 ;9/#9(;7 :1<9/#9287 ;9/
9&( ;9
9,1 ;9/#9(;7 3149/#9287 39/
9&( 39
9,1 9R.4159/#9&( 39→9R.4159
IXQFWLRQ
$W#;3(#RI#ULVLQJ
'HWHFWRU#7KUHVKROG
9R
9R×
4135
833
0318
$
9,1 9R.4159/#9&( 9R.4159→39
SSP2
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933
$
9'287 3149
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3
318
&
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043
09
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9
)
9
53
318
3
415
31;
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58
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6
9
43
)
PV
4
5
7
*
PV
3
318
,
—$
,
P$
-
9
9,1 9287 9&( 9'287 ;9
9,1 9287 5169/#9&( 39/
9
473
31;
316
Unit
9
433
'HOD\#7LPH#E\#6RIW06WDUW
9'287#´/µ#2XWSXW#&XUUHQW
4615
3
9287 46159
$SSOLHG#WR#%#DQG#)#YHUVLRQV#RQO\
&XUUHQW
43
9,1 46159/#9&( 46159/
9)0#'XW\#&\FOH
9'287#2XWSXW#/HDNDJH
MAX. Note*
“316
9,1 46159/#9&( 39/#9287 39
&\FOH
FLUFXLW
733
9287 46159
2VFLOODWRU#0D[LPXP#'XW\
'HOD\#7LPH#IRU#SURWHFWLRQ
TYP.
“433
9,1 46159/#9&( 46159/
6WDQGE\#&XUUHQW
7SURW
31<;
073ƒ&≤7RSW≤;8ƒ&
,VWE
7VWDUW
9R×
073ƒ&≤7RSW≤;8ƒ&
6XSSO\#&XUUHQW4
9)0GW\
MIN.
516
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0D[GW\
+7RSW 58ƒ&,
318
9,1 99/#9&( 99/
9'×
9287 9'×4159→39
31<;
4
9'
9'×
4135
7
R1221N
Symbol
79'(7
9+<6
∆09'(72
∆7
Item
Conditions
MIN.
TYP.
MAX. Note*
418
618
913
9,1 99/#9&( 99/
2XWSXW#'HOD\#7LPH#IRU
9287 39→9'×4159
5HOHDVHG#9ROWDJH
-
PV
-
P9
$W#;3(#RI#ULVLQJ
'HWHFWRU#7KUHVKROG#+\V0
9,1 99/#9&( 99/
9'×
9'×
9'×
WHUHVLV
9287 39→9'×4159
3134
3136
3138
'HWHFWRU#7KUHVKROG#7HP0
SHUDWXUH#&RHIILFLHQW
073ƒ&≤7RSW≤;8ƒ&
SSP2
“433
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1RWH=#5HIHU#WR#7HVW#&LUFXLWV
TEST CIRCUITS
A)
2
3
1
6
4
2
5
V
SD
4
A
VEXT
6
1
VIN
CIN
D)
L
PMOS
3
VIN
CL
VOUT
5
OSCILLOSCOPE
B)
E)
3
A
1
6
C)
3
1
6
4
2
5
VIN
VIN
4
CIN
A
2
3
1
6
4
2
5
A
5
F)
L
PMOS
VIN
3
1
6
V
VIN
CIN
SD
4
2
CL
5
OSCILLOSCOPE
8
Unit
R1221N
G)
I)
OSCILLOSCOPE
3
1
6
3
1
6
4
2
5
VIN
VIN
VOUT
4
2
5
VDOUT
A
H)
3
1
6
4
2
5
J)
A
VIN
3
1
6
VOUT
VIN
VOUT
4
2
5
R
OSCILLOSCOPE
,QGXFWRU#
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&DSDFLWRU#
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&,1#=#55—)#+7DQWDOXP#W\SH,
3RZHU#026#3026#=#+$743535#++LWDFKL,
5HVLVWRU#5#=#433NΩ
TYPICAL APPLICATIONS AND APPLICATION HINTS
PMOS
L
VIN
CIN
EXT
VCC
VOUT
SD1
CE
GND
COUT
R1
Reset/
VDOUT
CE CONTROL
CPU
3026=#+$743535#++LWDFKL,/#6L6776'9#+6LOLFRQL[,
/
6'4# =#5%7<4'#+5RKP,
&287#=#7:—)#+7DQWDOXP#7\SH,
&,1#
54
=43—)#+7DQWDOXP#7\SH,
=#&'438#+6XPLGD/#5:—+,
=#433NΩ
9
R1221N
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• 6HWWLQJ#'HWHFWRU#WKUHVKROG#YROWDJH#UDQJH#GHSHQGV#RQ#2XWSXW#YROWDJH#RI#'&2'&#FRQYHUWHU1
5HOHDVH#9ROWDJH#IURP#5HVHW#FRQGLWLRQ#PXVW#QRW#EH#PRUH#WKDQ#2XWSXW#YROWDJH#RI#'&2'&#FRQYHUWHU1
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R1221N
✩
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OPERATION of step-down DC/DC converter and Output Current
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<Basic Circuit>
<Current through L>
IL
i1
ILmax
IOUT
ILmin
topen
L
LxTr
VOUT
VIN
i2
SD
CL
ton
toff
T=1/fosc
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• Discontinuous Conduction Mode and Continuous Conduction Mode
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R1221N
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OUTPUT CURRENT AND SELECTION OF EXTERNAL COMPONENTS
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12
R1221N
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External Components
1.
Inductor
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2
Diode
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4.
Lx Transistor
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13
R1221N
TYPICAL CHARACTERISTCS
1)
Output Voltage vs. Output Current
m
R1221N33AH
R1221N15XH
L=27 H
1.515
Output Voltage VOUT (V)
Output Voltage VOUT (V)
3.380
3.360
3.340
3.320
3.300
3.280
12V
3.260
8V
3.240
4.5V
3.220
3.200
1E-05
0.0001
0.001
0.01
0.1
1.510
1.505
1.500
13.2V
1.495
8V
1.490
5V
1.485
2.3V
1.480
1E-05
1
0.0001
Output Current IOUT (A)
2)
0.001
0.01
0.1
1
Output Current IOUT (A)
Efficiency vs. Output Current
CD104-27µH
100
90
90
80
80
70
70
Efficiency η(%)
Efficiency η(%)
100
60
50
40
30
60
50
40
30
20
20
10
10
0
0.1
1
10
100
0
0.1
1000
CD104-27µH
Si3443DV
100
80
80
Efficiency η(%)
Efficiency η(%)
10
100
1000
60
40
CD104-27µH
Si3443DV
R1221N33AB(VIN=12V)
100
60
40
20
20
0
0.1
1
Output Current IOUT (mA)
Output Current IOUT (mA)
R1221N33AC(VIN=4.5V)
CD104-27µH
Si3443DV
R1221N33AA(VIN=12V)
R1221N33AA(VIN=4.5V) Si3443DV
1
10
100
Output Current IOUT (mA)
14
L=27µH
1.520
3.400
1000
0
0.1
1
10
100
Output Current IOUT (mA)
1000
R1221N
CD104-27µH
Si3443DV
CD104-27µH
R1221N33AC(VIN=12V)
100
100
90
90
80
80
70
70
Efficiency η(%)
Efficiency η(%)
R1221N33AC(VIN=4.5V) Si3443DV
60
50
40
30
60
50
40
30
20
20
10
10
0
0.1
1
10
100
0
0.1
1000
CD104-27µH
Si3443DV
80
80
Efficiency η(%)
Efficiency η(%)
100
60
40
CD104-27µH
Si3443DV
60
40
1
10
100
0
0.1
1000
CD104-27µH
Si3443DV
R1221N50XB(VIN=6.0V)
1
10
100
1000
Output Current IOUT (mA)
Output Current IOUT (mA)
100
100
80
80
60
40
CD104-27µH
Si3443DV
R1221N50XB(VIN=12V)
Efficiency η(%)
Efficiency η(%)
1000
20
20
60
40
20
20
0
0.1
100
R1221N50XA(VIN=12V)
100
0
0.1
10
Output Current IOUT (mA)
Output Current IOUT (mA)
R1221N50XA(VIN=6.0V)
1
1
10
100
Output Current IOUT (mA)
1000
0
0.1
1
10
100
1000
Output Current IOUT (mA)
15
R1221N
CD104-27µH
Si3443DV
100
100
80
80
60
40
60
40
20
20
0
0.1
1
10
100
0
0.1
1000
10
100
1000
Ripple Voltage vs. Output Current
R1221N33AA
L=27µH
C=47µF(Ta)
R1221N33AA
180
180
VIN=4.5V
VIN=8V
140
VIN=12V
120
VIN=6V
160
Ripple Voltage Vrpp (mV)
Ripple Voltage Vrpp (mV)
160
100
80
60
40
VIN=8V
140
VIN=12V
120
100
80
60
40
20
20
0
0
1
10
100
1
1000
R1221N33AB
10
100
1000
Output Current IOUT (mA)
Output Current IOUT (mA)
L=27µH
C=47µF(Ta)
R1221N50XB
200
L=27µH
C=47µF(Ta)
200
180
180
VIN=4.5V
160
140
VIN=6V
160
VIN=8V
Ripple Voltage Vrpp (mV)
Ripple Voltage Vrpp (mV)
L=27µH
C=47µF(Ta)
200
200
VIN=12V
120
100
80
60
40
20
VIN=8V
140
VIN=12V
120
100
80
60
40
20
0
0
1
10
100
Output Current IOUT (mA)
16
1
Outpur Current IOUT (mA)
Outpur Current IOUT (mA)
3)
CD104-27µH
Si3443DV
R1221N50XC(VIN=12V)
Efficiency η(%)
Efficiency η(%)
R1221N50XC(VIN=6.0V)
1000
1
10
100
Output Current IOUT (mA)
1000
R1221N
L=27µH
C=47µF(Ta)
R1221N33AC
200
200
180
140
VIN=6V
160
VIN=8V
Ripple Voltage Vrpp (mV)
Ripple Voltage Vrpp (mV)
180
VIN=4.5V
160
VIN=12V
120
100
80
60
40
VIN=8V
140
VIN=12V
120
100
80
60
40
20
20
0
0
1
10
100
1
1000
Oscillator Frequency vs. Input Voltage
R1221N15XB
Oscillator Frequency fosc(kHz)
Oscillator Frequency fosc(kHz)
500
400
300
200
100
0
5
10
L=27µH
500
400
300
200
100
0
15
0
5
10
15
Input Voltage VIN (V)
R1221N15XA
L=27µH
1.53
1.53
1.52
1.52
Output Voltage VOUT(V)
Output Voltage VOUT(V)
Output Voltage vs. Input Voltage
R1221N15XB
1.51
1.50
1.49
1.48
1.47
1000
600
Input Voltage VIN (V)
5)
100
R1221N15XA
L=27µH
600
0
10
Output Current IOUT (mA)
Output Current IOUT (mA)
4)
L=27µH
C=47µF(Ta)
R1221N50XC
L=27µH
1.51
1.50
1.49
1.48
0
5
10
Input Voltage VIN (V)
15
1.47
0
5
10
15
Input Voltage VIN (V)
17
R1221N
R1221N33AA
L=27µH
3.36
3.34
3.34
Output Voltage VOUT(V)
Output Voltage VOUT(V)
R1221N33AB
3.36
3.32
3.30
3.28
3.26
3.24
0
5
10
3.32
3.30
3.28
3.26
3.24
15
0
Input Voltage VIN (V)
6)
10
R1221N15XB
L=27µH
15
3.30
3.29
3.28
3.27
-50
0
50
1.50
1.49
1.48
1.47
-50
100
Temperature Topt (°C)
Detector Threshold vs. Temperature
R1221N25XA(VD=2.0V)
50
R1221N15XB(VD=1.2V)
VIN=6V
100
VIN=6V
1.22
Detector Threshold VDOUT(V)
Detector Threshold VDOUT(V)
0
Temperature Topt (°C)
2.01
2.00
1.99
1.98
1.97
-50
L=27µH
VIN=2.7V
1.51
Output Voltage VOUT(V)
Output Voltage VOUT(V)
3.31
0
50
Temperature Topt (°C)
18
5
Input Voltage VIN (V)
Output Voltage vs. Temperature
R1221N33AH
7)
L=27µH
100
1.21
1.20
1.19
1.18
-50
0
50
Temperature Topt (°C)
100
R1221N
R1221N33AB(VD=3.0V)
VIN=6V
Detector Threshold VDOUT(V)
3.06
3.04
3.02
3.00
2.98
2.96
2.94
-50
0
50
100
Temperature Topt (°C)
8)
Oscillator Frequency vs. Temperature
L=27µH
VIN=4.5V
R1221N33AB
R1221N25XA
360
Oscillator Frequency fosc(kHz)
Oscillator Frequency fosc(kHz)
600
550
500
450
400
-50
0
50
340
320
300
280
260
240
-50
100
0
50
100
Temperature Topt (°C)
Temperature Topt (°C)
Supply Current vs. Temperature
R1221N33AH
R1221N33AG
135
100
130
90
125
Supply Current1 (µA)
Supply Current1 (µA)
9)
L=27µH
VIN=3.7V
120
115
VIN=15V
110
VIN=13.2V
105
VIN=8V
100
VIN=15V
80
VIN=13.2V
70
VIN=8V
60
95
90
-50
0
50
Temperature Topt (°C)
100
50
-50
0
50
100
Temperature Topt (°C)
19
R1221N
10) Soft-start Time vs. Temperature
L=27µH
VIN=4.5V
R1221N33AB
8
10
Soft-start Time (msec)
12
Soft-start Time (msec)
10
6
4
8
6
4
2
0
-50
0
50
2
-50
100
R1221N25XA
4.0
4.0
3.5
3.5
Delay Time for Latch-type
Protection (msec)
Delay Time for Latch-type
Protection (msec)
11) Delay Time for Latch-type Protection vs. Temperature
VIN=4.5V
R1221N33AB
3.0
2.5
2.0
1.5
1.0
2.5
2.0
1.5
1.0
0
50
0.0
-50
100
0
R1221N33AG
5
4
4
Delay Time for Reset-type
Protection (msec)
5
3
2
1
0
50
Temperature Topt (°C)
50
100
Temperature Topt (°C)
12) Delay Time for Reset-type Protection vs. Temperature
R1221N33AH
VIN=4.5V
Delay Time for Reset-type
Protection (msec)
VIN=3.7V
3.0
Temperature Topt (°C)
20
100
0.5
0.5
0
-50
50
0
Temperature Topt (°C)
Temperature Topt (°C)
0.0
-50
L=27µH
VIN=3.7V
R1221N25XA
100
VIN=4.5V
3
2
1
0
-50
0
50
Temperature Topt (°C)
100
R1221N
13) VD Output Delay Time vs. Temperature
R1221N33AB
R1221N25XA
VIN=8.0V
5
4
3
2
1
0
-50
0
50
5
4
3
2
1
0
-50
100
Temperature Topt (°C)
50
100
15) EXT "L" Output Current vs. Temperature
R1221N33AB
16
30
EXT"L" Output Current (mA)
14
EXT"H"Output Current (mA)
0
Temperature Topt (°C)
14) EXT"H" Output Current vs. Temperature
R1221N33AB
12
10
8
6
4
2
0
-50
VIN=8.0V
6
VD Output Delay Time (msec)
VD Output Delay Time (msec)
6
0
50
100
Temperature Topt (°C)
25
20
15
10
5
0
-50
0
50
100
Temperature Topt (°C)
16) VDOUT "L" Output Current vs. Temperature
R1221N33AD
1.6
1.4
VDLC (mA)
1.2
1.0
0.8
0.6
0.4
0.2
0.0
-50
0
50
100
Temperature Topt (°C)
21
R1221N
17) Load Transient Response
R1221N33AA
VIN=5V
L=27µH
R1221N33AA
VIN=5V
L=27µH
3.6
3.4
3
500
2.6
2.4
0
0.0005
3.4
3.3
3.2
3.1
3
2.9
2.8
2.7
0.1
0.001
2.6
0
R1221N33AB
3.3
3.5
3.2
3.4
3.1
3
500
2.9
2.6
2.5
2.4
0
0.0005
2
3
2.9
2.7
2.6
0
3.4
3.1
3
500
2.9
2.4
0
0.0005
Time (sec)
0.1
0.001
VIN=5V
L=27µH
3.3
2
500
3.1
Output Current
IOUT(mA)
2.5
Output Voltage VOUT(V)
3.5
3.2
Output Current
IOUT(mA)
Output Voltage VOUT(V)
R1221N33AC
3.3
2.6
22
VIN=5V
L=27µH
3.6
2.7
0.1
0.1
0.05
Time (sec)
3.4
2.8
500
3.1
2.8
0.1
0.001
VIN=5V
L=27µH
3.3
Time (sec)
R1221N33AC
0.1
Output Current
IOUT(mA)
2.7
Output Voltage VOUT(V)
3.6
Output Current
IOUT(mA)
Output Voltage VOUT(V)
VIN=5V
L=27µH
3.4
2.8
0.1
0.05
Time (sec)
Time (sec)
R1221N33AB
500
Output Current
IOUT(mA)
2.8
Output Voltage VOUT(V)
3.2
Output Current
IOUT(mA)
Output Voltage VOUT(V)
3.5
3
2.9
2.8
2.7
2.6
0
0.05
Time (sec)
0.1
0.1
R1221N
VIN=5V
L=27µH
R1221N33AD
3.6
3.3
3.5
3.2
3.4
3.1
3
500
2.9
2.7
2.6
2.5
2.4
0
0.0005
3.3
2
500
3.1
3
2.9
2.8
2.7
0.1
0.001
2.6
0
Time (sec)
R1221N33AA(VIN=5V,IOUT=0mA)
10
0
0.01
0.02
3.5
3
2.5
2
1.5
1
0.5
0
-0.5
-1
-1.5
-2
-2.5
-3
-3.5
-0.01
5
0
0
Time (sec)
Time (sec)
0.02
Output Voltage VOUT(V)
Output Voltage VOUT(V)
0.02
3.5
3
2.5
2
1.5
1
0.5
0
-0.5
-1
-1.5
-2
-2.5
-3
-3.5
-0.01
L=27µH
5
CE
Voltage(V)
CE
Voltage(V)
0
0.01
R1221N33AB(VIN=5V,IOUT=0mA)
L=27µH
10
0
0.01
Time (sec)
R1221N33AB(VIN=10V,IOUT=0mA)
3.5
3
2.5
2
1.5
1
0.5
0
-0.5
-1
-1.5
-2
-2.5
-3
-3.5
-0.01
L=27µH
CE
Voltage (V)
Output Voltage VOUT(V)
L=27µH
CE
Voltage(V)
Output Voltage VOUT(V)
18) Turn-on Waveform
R1221N33AA(VIN=10V,IOUT=0mA)
0
0.1
0.1
0.05
Time (sec)
3.5
3
2.5
2
1.5
1
0.5
0
-0.5
-1
-1.5
-2
-2.5
-3
-3.5
-0.01
VIN=5V
L=27µH
Output Current
IOUT(mA)
2.8
Output Voltage VOUT(V)
3.4
Output Current
IOUT(mA)
Output Voltage VOUT(V)
R1221N33AD
0
0
0.01
0.02
Time (sec)
23
R1221N
R1221N33AA(VIN=5V,IOUT=100mA)
10
0
0
0.01
0.02
3.5
3
2.5
2
1.5
1
0.5
0
-0.5
-1
-1.5
-2
-2.5
-3
-3.5
-0.01
5
0
0
Time (sec)
0.01
0.02
Output Voltage VOUT(V)
Output Voltage VOUT(V)
24
0.02
3.5
3
2.5
2
1.5
1
0.5
0
-0.5
-1
-1.5
-2
-2.5
-3
-3.5
-0.01
L=27µH
5
CE
Voltage(V)
CE
Voltage(V)
0
Time (sec)
R1221N33AB(VIN=5V,IOUT=100mA)
L=27µH
10
0
0.01
Time (sec)
R1221N33AB(VIN=10V,IOUT=100mA)
3.5
3
2.5
2
1.5
1
0.5
0
-0.5
-1
-1.5
-2
-2.5
-3
-3.5
-0.01
L=27µH
CE
Voltage(V)
Output Voltage VOUT(V)
L=27µH
CE
Voltage(V)
Output Voltage VOUT(V)
R1221N33AA(VIN=10V,IOUT=100mA)
3.5
3
2.5
2
1.5
1
0.5
0
-0.5
-1
-1.5
-2
-2.5
-3
-3.5
-0.01
0
0
0.01
Time (sec)
0.02