R1221N37XD-TR [ETC]
SMPS Controller ; SMPS控制器\n型号: | R1221N37XD-TR |
厂家: | ETC |
描述: | SMPS Controller
|
文件: | 总25页 (文件大小:252K) |
中文: | 中文翻译 | 下载: | 下载PDF数据表文档文件 |
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
7KH#545541#6HULHV#DUH#3:0#VWHS0GRZQ#'&2'&#&RQYHUWHU#FRQWUROOHUV#HPEHGGHG#ZLWK#D#YROWDJH#GHWHFWRU/#ZLWK#ORZ
VXSSO\#FXUUHQW#E\#&026#SURFHVV1
(DFK#VWHS0GRZQ#'&2'&#FRQYHUWHU#LQ#WKHVH#,&V#FRQVLVWV#RI#DQ#RVFLOODWRU/#D#3:0#FRQWURO#FLUFXLW/#D#UHIHUHQFH#YROWDJH
XQLW/#DQ#HUURU#DPSOLILHU/#D#VRIW0VWDUW#FLUFXLW/#D#SURWHFWLRQ#FLUFXLW/#D#3:029)0#DOWHUQDWLYH#FLUFXLW/#D#FKLS#HQDEOH#FLUFXLW/
DQG#UHVLVWRUV#IRU#YROWDJH#GHWHFWLRQ1#$#ORZ#ULSSOH/#KLJK#HIILFLHQF\#VWHS0GRZQ#'&2'&#FRQYHUWHU#FDQ#EH#FRPSRVHG#RI#WKLV
,&#ZLWK#RQO\#IRXU#H[WHUQDO#FRPSRQHQWV/#RU#D#SRZHU0WUDQVLVWRU/#DQ#LQGXFWRU/#D#GLRGH#DQG#D#FDSDFLWRU1
7KH#RXWSXW#YROWDJH#RI#'&2'&#FRQYHUWHU#FDQ#EH#VXSHUYLVHG#E\#WKH#EXLOW0LQ#YROWDJH#GHWHFWRU1
:LWK#D#3:029)0#DOWHUQDWLYH#FLUFXLW/#ZKHQ#WKH#ORDG#FXUUHQW#LV#VPDOO/#WKH#RSHUDWLRQ#WXUQV#LQWR#WKH#9)0#RVFLOODWRU
IURP#3:0#RVFLOODWRU#DXWRPDWLFDOO\/#WKHUHIRUH#WKH#HIILFLHQF\#DW#VPDOO#ORDG#FXUUHQW#LV#LPSURYHG1
$QG#WKH#3:029)0#DOWHUQDWLYH#FLUFXLW#LV#DQ#RSWLRQ/#LQ#WHUPV#RI#&#YHUVLRQ#DQG#'#YHUVLRQ/#WKH#FLUFXLW#LV#QRW#LQFOXGHG1
,I#WKH#WHUP#RI#PD[LPXP#GXW\#F\FOH#NHHSV#RQ#D#FHUWDLQ#WLPH/#WKH#HPEHGGHG#SURWHFWLRQ#FLUFXLW#ZRUNV1#7KHUH#DUH#WZR
W\SHV#RI#SURWHFWLRQ#IXQFWLRQ1#2QH#LV#ODWFK0W\SH#SURWHFWLRQ#FLUFXLW/#DQG#LW#ZRUNV#WR#ODWFK#DQ#H[WHUQDO#3RZHU#026#ZLWK
NHHSLQJ#LW#GLVDEOH1#7R#UHOHDVH#WKH#FRQGLWLRQ#RI#SURWHFWLRQ/#DIWHU#GLVDEOH#WKLV#,&#ZLWK#D#FKLS#HQDEOH#FLUFXLW/#HQDEOH#LW#DJDLQ/
RU#UHVWDUW#WKLV#,&#ZLWK#SRZHU0RQ1#7KH#RWKHU#LV#5HVHW0W\SH#SURWHFWLRQ#FLUFXLW/#DQG#LW#ZRUNV#WR#UHVWDUW#WKH#RSHUDWLRQ#ZLWK
VRIW0VWDUW#DQG#UHSHDW#WKLV#RSHUDWLRQ#XQWLO#PD[LPXP#GXW\#F\FOH#FRQGLWLRQ#LV#UHOHDVHG1#(LWKHU#RI#WKHVH#SURWHFWLRQ#FLUFXLWV
FDQ#EH#GHVLJQDWHG#E\#XVHUV*#UHTXHVW1
FEATURES
• :LGH#5DQJH#RI#,QSXW#9ROWDJH 111111111111111111111111111111111111111111111 5169#WR#46159
• %XLOW0LQ#6RIW0VWDUW#)XQFWLRQ#DQG#WZR#FKRLFHV#RI#3URWHFWLRQ#)XQFWLRQ#+/DWFK0W\SH#RU#5HVHW0W\SH,
• 7Z R #FKRLFHV#RI#2VFLOODWRU#)UHTXHQF\11111111111111111111111111111111 633N+]/#833N+]
• +LJK#(IILFLHQF\ 111111111111111111111111111111111111111111111111111111111111111111 7<31#<3(
• 6WDQGE\#&XUUHQW 1111111111111111111111111111111111111111111111111111111111111111 7<31#3µ$
• 6HWWLQJ#2XWSXW#9ROWDJH 111111111111111111111111111111111111111111111111111111 6WHSZLVH#VHWWLQJ#ZLWK#D#VWHS#RI#3149#LQ#WKH#UDQJH#RI#4189
WR#8139
• +LJK#$FFXUDF\#2XWSXW#9ROWDJH 11111111111111111111111111111111111111111 ±513(
• 6HWWLQJ#'HWHFWRU#7KUHVKROG#9ROWDJH 111111111111111111111111111111111 6WHSZLVH#VHWWLQJ#ZLWK#D#VWHS#RI#3149#LQ#WKH#UDQJH#RI#4159
WR#7189
• +LJK#$FFXUDF\#'HWHFWRU#7KUHVKROG#9ROWDJH 11111111111111111111 ±513(
• /RZ#7HPSHUDWXUH0'ULIW#&RHIILFLHQW#RI#2XWSXW#9ROWDJH 1111 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
V
IN
V
OUT
EXT
Vref
PWM/VFM
CONTROL
Protection
Soft Start
Chip Enable
CE
Vref
VDOUT
GND
2
R1221N
SELECTION GUIDE
,Q#WKH#545541#6HULHV/#WKH#RXWSXW#YROWDJH/#WKH#GHWHFWRU#WKUHVKROG/#WKH#RVFLOODWRU#IUHTXHQF\/#WKH#RSWLRQDO#IXQFWLRQ/#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>
545541;;;;075
↑ ↑ ↑
D E F
Code
Contents
6HWWLQJ#2XWSXW#9ROWDJH#+9287,=
D
6WHSZLVH#VHWWLQJ#ZLWK#D#VWHS#RI#3149#LQ#WKH#UDQJH#RI#4189#WR#8139#LV#SRVVLEOH1
6HWWLQJ#'HWHFWRU#7KUHVKROG#+09'(7,
E
F
6WHSZLVH#VHWWLQJ#ZLWK#D#VWHS#RI#3149#LQ#WKH#UDQJH#RI#4159#WR#7189#LV#SRVVLEOH1
$#=#6139
'HVLJQDWLRQ#RI#2VFLOODWRU#)UHTXHQF\#DQG#2SWLRQDO#)XQFWLRQ
$#=#633N+]/#ZLWK#D#3:029)0#DOWHUQDWLYH#FLUFXLW/#/DWFK0W\SH#SURWHFWLRQ
%#=#833N+]/#ZLWK#D#3:029)0#DOWHUQDWLYH#FLUFXLW/#/DWFK0W\SH#SURWHFWLRQ
&#=#633N+]/#ZLWKRXW#D#3:029)0#DOWHUQDWLYH#FLUFXLW/#/DWFK0W\SH#SURWHFWLRQ
'#=#833N+]/#ZLWKRXW#D#3:029)0#DOWHUQDWLYH#FLUFXLW/#/DWFK0W\SH#SURWHFWLRQ
(#=#633N+]/#ZLWK#D#3:029)0#DOWHUQDWLYH#FLUFXLW/#5HVHW0W\SH#SURWHFWLRQ
)#=#833N+]/#ZLWK#D#3:029)0#DOWHUQDWLYH#FLUFXLW/#5HVHW0W\SH#SURWHFWLRQ
*#=#633N+]/#ZLWKRXW#D#3:029)0#DOWHUQDWLYH#FLUFXLW/#5HVHW0W\SH#SURWHFWLRQ
+#=#833N+]/#ZLWKRXW#D#3:029)0#DOWHUQDWLYH#FLUFXLW/#5HVHW0W\SH#SURWHFWLRQ
PIN CONFIGURATION
SOT-23-6W
6
5
4
VOUT GND CE
(mark side)
EXT VDOUT
VIN
1
2
3
3
R1221N
PIN DESCRIPTION
Pin No.
Symbol
(;7
9'287
9,1
Description
([WHUQDO#7UDQVLVWRU#'ULYH#3LQ#+2XWSXW#7\SH#>#&026,
9ROWDJH#'HWHFWRU#2XWSXW#3LQ#+2XWSXW#7\SH#>#1FK#2SHQ#'UDLQ,
3RZHU#6XSSO\#3LQ
4
5
6
7
8
9
&(
&KLS#(QDEOH#3LQ
*1'
9287
*URXQG#3LQ
3LQ#IRU#0RQLWRULQJ#2XWSXW#9ROWDJH
ABSOLUTE MAXIMUM RATING
Symbol
Item
Rating
48
Unit
9
9,1
9,1#6XSSO\#9ROWDJH
9(;7
9&(
(;7#3LQ#2XWSXW#9ROWDJH
&(#3LQ#,QSXW#9ROWDJH
0316 9,1.316
0316 9,1.316
0316 48
9
9
9'287
9287
,(;7
9'287#3LQ#2XWSXW#9ROWDJH
9287#3LQ#,QSXW#9ROWDJH
9
0316 9,1.316
“58
9
(;7#3LQ#,QGXFWRU#'ULYH#2XWSXW#&XUUHQW
3RZHU#'LVVLSDWLRQ
P$
P:
ƒ&
ƒ&
3'
583
7RSW
7VWJ
2SHUDWLQJ#7HPSHUDWXUH#5DQJH
6WRUDJH#7HPSHUDWXUH#5DQJH
073 .;8
088 .458
4
R1221N
ELECTRICAL CHARACTERISTICS
• R1221N***A (C,E,G) Output Voltage : Vo, Detector Threshold : VD
+7RSW 58ƒ&,
Symbol
Item
Conditions
MIN. TYP. MAX. Note* Unit
9,1
2SHUDWLQJ#,QSXW#9ROWDJH
516
4615
9
9
9R×
9R×
9287
6WHS0GRZQ#2XWSXW#9ROWDJH 9,1 9&( 9R.4159/#,287 043P$
9R
$
$
31<;
4135
∆92872
∆7
6WHS0GRZQ#2XWSXW#9ROWDJH
073ƒ&≤7RSW≤;8ƒ&
SSP2
“433
633
7HPSHUDWXUH#&RHIILFLHQW
ƒ&
IRVF
2VFLOODWRU#)UHTXHQF\
9,1 9&( 9R.4159/#,287 0433P$
073ƒ&≤7RSW≤;8ƒ&
573
693
N+]
∆IRVF2
∆7
)UHTXHQF\#7HPSHUDWXUH
“316
(2ƒ&
&RHIILFLHQW
9,1 46159/#9&( 46159/
9287 46159
,''4
,VWE
6XSSO\#&XUUHQW4
433
3
493
318
09
%
&
'
—$
—$
6WDQGE\#&XUUHQW
9,1 46159/#9&( 39/#9287 39
9,1 ;9/#9(;7 :1<9/#9287 ;9/
9&( ;9
,(;7+
(;7#´+µ#2XWSXW#&XUUHQW
043
P$
9,1 ;9/#9(;7 3149/#9287 39/
9&( 39
,(;7/
(;7#´/µ#2XWSXW#&XUUHQW
&(#´+µ#,QSXW#&XUUHQW
43
53
3
'
(
P$
—$
9,1 46159/#9&( 46159/
9287 46159
,&(+
318
415
,&(/
9&(+
9&(/
&(#´/µ#,QSXW#&XUUHQW
&(#´+µ#,QSXW#9ROWDJH
&(#´/µ#,QSXW#9ROWDJH
9,1 46159/#9&( 39/#9287 46159
9,1 ;9/#9&( 39→4189
0318
3
(
)
)
—$
9
31;
31;
9,1 ;9/#9&( 4189→39
316
9
2VFLOODWRU#0D[LPXP#'XW\
0D[GW\
433
(
(
&\FOH
9)0GW\ 9)0#'XW\#&\FOH
'HOD\#7LPH#E\#6RIW06WDUW
$SSOLHG#WR#%#DQG#)#YHUVLRQV#RQO\
58
43
9,1 9R.4159/#9&( 39→9R.4159
$W#;3(#RI#ULVLQJ
7VWDU W
7SURW
,9'/.
,9'/
8
4
49
8
)
*
,
PV
IXQFWLRQ
'HOD\#7LPH#IRU#SURWHFWLRQ
9,1 9R.4159/#9&( 9R.4159→39
9,1 9287 9&( 9'287 ;9
6
3
4
PV
—$
FLUFXLW
9'287#2XWSXW#/HDNDJH
318
&XUUHQW
9,1 9287 5169/#9&( 39/
9'287 3149
9'287#´/µ#2XWSXW#&XUUHQW
318
,
P$
5
R1221N
Symbol
Item
Conditions
9,1 99/#9&( 99/
MIN. TYP. MAX. Note* Unit
9'×
9'×
09'(7
'HWHFWRU#7KUHVKROG
9'
-
-
-
9
9287 9'×4159→39
31<;
4135
9,1 99/#9&( 99/
9287 39→9'×4159
$W#;3(#RI#ULVLQJ
2XWSXW#'HOD\#7LPH#IRU
5HOHDVHG#9ROWDJH
W9'(7
5
8
43
PV
P9
'HWHFWRU#7KUHVKROG#+\V0
9,1 99/#9&( 99/
9'×
9'×
9'×
9+<6
WHUHVLV
9287 39→9'×4159
3134
3136
3138
∆09'(72 'HWHFWRU#7KUHVKROG#7HP0
∆7 SHUDWXUH#&RHIILFLHQW
1RWH=#5HIHU#WR#7HVW#&LUFXLWV
SSP2
073ƒ&≤7RSW≤;8ƒ&
“433
ƒ&
6
R1221N
• R1221N***B (D,F,H) Output Voltage : Vo, Detector Threshold : VD
+7RSW 58ƒ&,
Symbol
Item
Conditions
MIN. TYP. MAX. Note* Unit
9,1
2SHUDWLQJ#,QSXW#9ROWDJH
516
4615
9
9
9R×
9R×
9287
6WHS0GRZQ#2XWSXW#9ROWDJH 9,1 9&( 9R.4159/#,287 043P$
9R
$
$
31<;
4135
∆92872
∆7
6WHS0GRZQ#2XWSXW#9ROWDJH
073ƒ&≤7RSW≤;8ƒ&
SSP2
“433
833
7HPSHUDWXUH#&RHIILFLHQW
ƒ&
IRVF
2VFLOODWRU#)UHTXHQF\
9,1 9&( 9R.4159/#,287 0433P$
073ƒ&≤7RSW≤;8ƒ&
733
933
N+]
)UHTXHQF\#7HPSHUDWXUH
∆IRVF2∆7
“316
(2ƒ&
&RHIILFLHQW
9,1 46159/#9&( 46159/
9287 46159
,''4
,VWE
6XSSO\#&XUUHQW4
473
3
533
318
09
%
&
'
—$
—$
6WDQGE\#&XUUHQW
9,1 46159/#9&( 39/#9287 39
9,1 ;9/#9(;7 :1<9/#9287 ;9/
9&( ;9
,(;7+
(;7#´+µ#2XWSXW#&XUUHQW
043
P$
9,1 ;9/#9(;7 3149/#9287 39/
9&( 39
,(;7/
(;7#´/µ#2XWSXW#&XUUHQW
&(#´+µ#,QSXW#&XUUHQW
43
53
3
'
(
P$
—$
9,1 46159/#9&( 46159/
9287 46159
,&(+
318
415
,&(/
9&(+
9&(/
&(#´/µ#,QSXW#&XUUHQW
&(#´+µ#,QSXW#9ROWDJH
&(#´/µ#,QSXW#9ROWDJH
9,1 46159/#9&( 39/#9287 46159
9,1 ;9/#9&( 39→4189
0318
3
(
)
)
—$
9
31;
31;
9,1 ;9/#9&( 4189→39
316
9
2VFLOODWRU#0D[LPXP#'XW\
0D[GW\
433
(
(
&\FOH
9)0GW\ 9)0#'XW\#&\FOH
'HOD\#7LPH#E\#6RIW06WDUW
$SSOLHG#WR#%#DQG#)#YHUVLRQV#RQO\
58
9
9,1 9R.4159/#9&( 39→9R.4159
$W#;3(#RI#ULVLQJ
7VWDU W
7SURW
,9'/.
,9'/
6
4
43
7
)
*
,
PV
IXQFWLRQ
'HOD\#7LPH#IRU#SURWHFWLRQ
9,1 9R.4159/#9&( 9R.4159→39
9,1 9287 9&( 9'287 ;9
5
3
PV
—$
P$
9
FLUFXLW
9'287#2XWSXW#/HDNDJH
318
&XUUHQW
9,1 9287 5169/#9&( 39/
9'287 3149
9'287#´/µ#2XWSXW#&XUUHQW
'HWHFWRU#7KUHVKROG
318
4
,
9,1 99/#9&( 99/
9'×
9'×
09'(7
9'
-
9287 9'×4159→39
31<;
4135
7
R1221N
Symbol
Item
Conditions
9,1 99/#9&( 99/
MIN. TYP. MAX. Note* Unit
2XWSXW#'HOD\#7LPH#IRU
5HOHDVHG#9ROWDJH
79'(7
9287 39→9'×4159
$W#;3(#RI#ULVLQJ
418
618
913
-
-
PV
'HWHFWRU#7KUHVKROG#+\V0
9,1 99/#9&( 99/
9'×
9'×
9'×
9+<6
P9
WHUHVLV
9287 39→9'×4159
3134
3136
3138
∆09'(72 'HWHFWRU#7KUHVKROG#7HP0
∆7 SHUDWXUH#&RHIILFLHQW
SSP2
073ƒ&≤7RSW≤;8ƒ&
“433
ƒ&
1RWH=#5HIHU#WR#7HVW#&LUFXLWV
TEST CIRCUITS
A)
D)
A
6
L
PMOS
VEXT
3
4
1
2
6
5
3
4
1
2
V
VIN
VOUT
CL
VIN
SD
5
CIN
OSCILLOSCOPE
B)
E)
3
4
1
2
6
5
3
4
1
2
6
5
A
V
IN
V
IN
A
CIN
C)
F)
A
L
3
1
6
PMOS
VIN
3
4
1
2
6
5
4
2
5
V
CIN
C
L
V
IN
SD
OSCILLOSCOPE
8
R1221N
G)
I)
3
4
1
2
6
5
OSCILLOSCOPE
3
4
1
2
6
5
V
IN
VIN
VOUT
VDOUT
A
H)
J)
A
3
1
2
6
5
3
4
1
2
6
5
V
OUT
V
IN
V
IN
V
OUT
4
R
OSCILLOSCOPE
,QGXFWRU#
/#=#5:—+#+6XPLGD#(OHFWURQLF/#&'437, 'LRGH#6' =#5%7<4'#+5RKP/#6FKRWWN\#W\SH,
&/=#7:—)#+7DQWDOXP#W\SH, &,1#=#55—)#+7DQWDOXP#W\SH,
5HVLVWRU#5#=#433NΩ
&DSDFLWRU#
3RZHU#026#3026#=#+$743535#++LWDFKL,
TYPICAL APPLICATIONS AND APPLICATION HINTS
PMOS
L
VCC
EXT
VIN
V
OUT
SD1
C
OUT
R1
CE
CIN
Reset/
VDOUT
GND
CE CONTROL
CPU
3026=#+$743535#++LWDFKL,/#6L6776'9#+6LOLFRQL[,
6'4# =#5%7<4'#+5RKP,
/
=#&'438#+6XPLGD/#5:—+,
&287#=#7:—)#+7DQWDOXP#7\SH,
54 =#433NΩ
&,1# =43—)#+7DQWDOXP#7\SH,
9
R1221N
:KHQ#\RX#XVH#WKHVH#,&V/#FRQVLGHU#WKH#IROORZLQJ#LVVXHV>
• $V#VKRZQ#LQ#WKH#EORFN#GLDJUDP/#D#SDUDVLWLF#GLRGH#LV#IRUPHG#LQ#HDFK#WHUPLQDO/#HDFK#RI#WKHVH#GLRGHV#LV#QRW#IRUPHG#IRU
ORDG#FXUUHQW/#WKHUHIRUH#GR#QRW#XVH#LW#LQ#VXFK#D#ZD\1#:KHQ#\RX#FRQWURO#WKH#&(#SLQ#E\#DQRWKHU#SRZHU#VXSSO\/#GR#QRW
PDNH#LWV#´+µ#OHYHO#PRUH#WKDQ#WKH#YROWDJH#OHYHO#RI#9,1#SLQ1
• 'HWHFWRU#WKUHVKROG#K\VWHUHVLV#LV#VHW#DW#6#SHUFHQW#RI#GHWHFWRU#WKUHVKROG#YROWDJH1#+0LQ1#4#SHUFHQW/#0D[1#8#SHUFHQW,
• 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
+'HWHFWRU#7KUHVKROG#9ROWDJH×413:#?#2XWSXW#9ROWDJH#RI#'&2'&#FRQYHUWHU×31<;
• :KHQ#WKH#545541;;;;#LV#RQ#VWDQG0E\#PRGH/#WKH#RXWSXW#YROWDJH#RI#9'287#LV#*1'#OHYHO/#WKHUHIRUH#LI#WKH#SXOO0XS#UH0
VLVWRU#IRU#9'287#SLQ#LV#SXOOHG#XS#DQRWKHU#SRZHU#VXSSO\/#D#FHUWDLQ#DPRXQW#RI#FXUUHQW#LV#ORDGLQJ#WKURXJK#WKH#UHVLVWRU1
• 7KH#RSHUDWLRQ#RI#/DWFK0W\SH#SURWHFWLRQ#FLUFXLW#LV#DV#IROORZV>
:KHQ#WKH#PD[LPXP#GXW\#F\FOH#FRQWLQXHV#ORQJHU#WKDQ#WKH#GHOD\#WLPH#IRU#SURWHFWLRQ#FLUFXLW/#+5HIHU#WR#WKH#(OHFWULFDO
&KDUDFWHULVWLFV,#WKH#SURWHFWLRQ#FLUFXLW#ZRUNV#WR#VKXW0GRZQ#WKH#H[WHUQDO#3RZHU#026#ZLWK#LWV#ODWFKLQJ#RSHUDWLRQ1
7KHUHIRUH#ZKHQ#DQ#LQSXW2RXWSXW#YROWDJH#GLIIHUHQFH#LV#VPDOO/#WKH#SURWHFWLRQ#FLUFXLW#PD\#ZRUN#HYHQ#DW#VPDOO#ORDG#FXU0
UHQW1
7R#UHOHDVH#WKH#SURWHFWLRQ#VWDWH/#DIWHU#GLVDEOH#WKLV#,&#ZLWK#D#FKLS#HQDEOH#FLUFXLW/#HQDEOH#LW#DJDLQ/#RU#UHVWDUW#WKLV#,&#ZLWK
SRZHU0RQ1#+RZHYHU/#LQ#WKH#FDVH#RI#UHVWDUWLQJ#WKLV#,&#ZLWK#SRZHU0RQ/#DIWHU#WKH#SRZHU#VXSSO\#LV#WXUQHG#RII/#LI#D#FHUWDLQ
DPRXQW#RI#FKDUJH#UHPDLQV#LQ#&,1/#RU#VRPH#YROWDJH#LV#IRUFHG#WR#9,1#IURP#&,1/#WKLV#,&#PLJKW#QRW#EH#UHVWDUWHG#HYHQ#DIWHU
SRZHU0RQ1
,I#ULVLQJ#WUDQVLWLRQ#VSHHG#RI#VXSSO\#YROWDJH#LV#WRR#VORZ/#RU#WKH#WLPH#ZKLFK#LV#UHTXLUHG#IRU#9,1#YROWDJH#WR#UHDFK#2XWSXW
9ROWDJH#RI#'&2'&#FRQYHUWHU#LV#ORQJHU#WKDQ#VRIW0VWDUWLQJ#WLPH#SOXV#GHOD\#WLPH#IRU#SURWHFWLRQ#FLUFXLW/#SURWHFWLRQ#FLUFXLW
ZRUNV#EHIRUH#9,1#YROWDJH#UHDFKHV#2XWSXW#9ROWDJH#RI#'&2'&#FRQYHUWHU1#7R#DYRLG#WKLV#FRQGLWLRQ/#PDNH#WKLV#,&#GLVDEOH
+&( ´/µ,#ILUVW/#WKHQ#IRUFH#9,1#YROWDJH/#DQG#DIWHU#9,1#YROWDJH#EHFRPHV#HTXDO#RU#PRUH#WKDQ#9287/#PDNH#WKLV#,&#HQDEOH
+&( ´+µ,1
• 6HW#H[WHUQDO#FRPSRQHQWV#DV#FORVH#DV#SRVVLEOH#WR#WKH#,&#DQG#PLQLPL]H#WKH#FRQQHFWLRQ#EHWZHHQ#WKH#FRPSRQHQWV#DQG
WKH#,&1#,Q#SDUWLFXODU/#D#FDSDFLWRU#VKRXOG#EH#FRQQHFWHG#WR#9287#SLQ#ZLWK#WKH#PLQLPXP#FRQQHFWLRQ1#$QG#PDNH#VXIILFLHQW
JURXQGLQJ#DQG#UHLQIRUFH#VXSSO\LQJ1#$#ODUJH#VZLWFKLQJ#FXUUHQW#IORZV#WKURXJK#WKH#FRQQHFWLRQ#RI#SRZHU#VXSSO\/#DQ#LQ0
GXFWRU#DQG#WKH#FRQQHFWLRQ#RI#92871#,I#WKH#LPSHGDQFH#RI#SRZHU#VXSSO\#OLQH#LV#KLJK/#WKH#YROWDJH#OHYHO#RI#SRZHU#VXSSO\#RI
WKH#,&#IOXFWXDWHV#ZLWK#WKH#VZLWFKLQJ#FXUUHQW1#7KLV#PD\#FDXVH#XQVWDEOH#RSHUDWLRQ#RI#WKH#,&1
• 8VH#FDSDFLWRUV#ZLWK#D#FDSDFLW\#RI#55—)#RU#PRUH#IRU#9287#3LQ/#DQG#ZLWK#JRRG#KLJK#IUHTXHQF\#FKDUDFWHULVWLFV#VXFK#DV
WDQWDOXP#FDSDFLWRUV1#:H#UHFRPPHQG#\RX#WR#XVH#FDSDFLWRUV#ZLWK#DQ#DOORZDEOH#YROWDJH#ZKLFK#LV#DW#OHDVW#WZLFH#DV#PXFK
DV#VHWWLQJ#RXWSXW#YROWDJH1#7KLV#LV#EHFDXVH#WKHUH#PD\#EH#D#FDVH#ZKHUH#D#VSLNH0VKDSHG#KLJK#YROWDJH#LV#JHQHUDWHG#E\#DQ
LQGXFWRU#ZKHQ#DQ#H[WHUQDO#WUDQVLVWRU#LV#RQ#DQG#RII1
• &KRRVH#DQ#LQGXFWRU#WKDW#KDV#VXIILFLHQWO\#VPDOO#'1&1#UHVLVWDQFH#DQG#ODUJH#DOORZDEOH#FXUUHQW#DQG#LV#KDUG#WR#UHDFK#PDJ0
QHWLF#VDWXUDWLRQ1#$QG#LI#WKH#YDOXH#RI#LQGXFWDQFH#RI#DQ#LQGXFWRU#LV#H[WUHPHO\#VPDOO/#WKH#,/;#PD\#H[FHHG#WKH#DEVROXWH
PD[LPXP#UDWLQJ#DW#WKH#PD[LPXP#ORDGLQJ1
8VH#DQ#LQGXFWRU#ZLWK#DSSURSULDWH#LQGXFWDQFH1
• 8VH#D#GLRGH#RI#D#6FKRWWN\#W\SH#ZLWK#KLJK#VZLWFKLQJ#VSHHG/#DQG#DOVR#SD\#DWWHQWLRQ#WR#LWV#FXUUHQW#FDSDFLW\1
• 'R#QRW#XVH#WKLV#,&#XQGHU#WKH#FRQGLWLRQ#DW#9,1#YROWDJH#OHVV#WKDQ#PLQLPXP#RSHUDWLQJ#YROWDJH1
10
R1221N
✩
7KH# SHUIRUPDQFH# RI# SRZHU# VRXUFH# FLUFXLWV# XVLQJ# WKHVH# ,&V# H[WUHPHO\# GHSHQGV# XSRQ# WKH# SHULSKHUDO# FLUFXLWV1
3D\#DWWHQWLRQ#LQ#WKH#VHOHFWLRQ#RI#WKH#SHULSKHUDO#FLUFXLWV1#,Q#SDUWLFXODU/#GHVLJQ#WKH#SHULSKHUDO#FLUFXLWV#LQ#D#ZD\#WKDW
WKH#YDOXHV#VXFK#DV#YROWDJH/#FXUUHQW/#DQG#SRZHU#RI#HDFK#FRPSRQHQW/#3&%#SDWWHUQV#DQG#WKH#,&#GR#QRW#H[FHHG#WKHLU
UHVSHFWHG#UDWHG#YDOXHV1
OPERATION of step-down DC/DC converter and Output Current
7KH#VWHS0GRZQ#'&2'&#FRQYHUWHU#FKDUJHV#HQHUJ\#LQ#WKH#LQGXFWRU#ZKHQ#/[#WUDQVLVWRU#LV#21/#DQG#GLVFKDUJHV#WKH#HQ0
HUJ\#IURP#WKH#LQGXFWRU#ZKHQ#/[#WUDQVLVWRU#LV#2))#DQG#FRQWUROV#ZLWK#OHVV#HQHUJ\#ORVV/#VR#WKDW#D#ORZHU#RXWSXW#YROWDJH
WKDQ#WKH#LQSXW#YROWDJH#LV#REWDLQHG1#7KH#RSHUDWLRQ#ZLOO#EH#H[SODLQHG#ZLWK#UHIHUHQFH#WR#WKH#IROORZLQJ#GLDJUDPV#=
<Basic Circuit>
<Current through L>
ILmax
IL
i1
I
OUT
ILmin
topen
L
LxTr
SD
VOUT
V
IN
i2
CL
ton
toff
T=1/fosc
6WHS#4#=/[7U#WXUQV#RQ#DQG#FXUUHQW#,/#+ L4,#IORZV/#DQG#HQHUJ\#LV#FKDUJHG#LQWR#&/1#$W#WKLV#PRPHQW/#,/#LQFUHDVHV#IURP
,/PLQ#+ 3,#WR#UHDFK#,/PD[#LQ#SURSRUWLRQ#WR#WKH#RQ0WLPH#SHULRG#+WRQ,#RI#/;7U1
6WHS#5#=:KHQ#/[7U#WXUQV#RII/#6FKRWWN\#GLRGH#+6',#WXUQV#RQ#LQ#RUGHU#WKDW#/#PDLQWDLQV#,/#DW#,/PD[/#DQG#FXUUHQW#,/#+ L5,
IORZV1
6WHS#6#=,/#GHFUHDVHV#JUDGXDOO\#DQG#UHDFKHV#,/PLQ#DIWHU#D#WLPH#SHULRG#RI#WRSHQ/#DQG#6'#WXUQV#RII/#SURYLGHG#WKDW#LQ#WKH
FRQWLQXRXV#PRGH/#QH[W#F\FOH#VWDUWV#EHIRUH#,/#EHFRPHV#WR#3#EHFDXVH#WRII#WLPH#LV#QRW#HQRXJK1#,Q#WKLV#FDVH/#,/
YDOXH#LV#IURP#WKLV#,/PLQ+!3,1
,Q#WKH#FDVH#RI#3:0#FRQWURO#V\VWHP/#WKH#RXWSXW#YROWDJH#LV#PDLQWDLQHG#E\#FRQWUROOLQJ#WKH#RQ0WLPH#SHULRG#+WRQ,/#VLWK
WKH#RVFLOODWRU#IUHTXHQF\#+IRVF,#EHLQJ#PDLQWDLQHG#FRQVWDQW1
• Discontinuous Conduction Mode and Continuous Conduction Mode
7KH#PD[LPXP#YDOXH#+,/PD[,#DQG#WKH#PLQLPXP#YDOXH#+,/PLQ,#RI#WKH#FXUUHQW#ZKLFK#IORZV#WKURXJK#WKH#LQGXFWRU#DUH
WKH#VDPH#DV#WKRVH#ZKHQ#/[7U#LV#21#DQG#ZKHQ#LW#LV#2))1
7KH#GLIIHUHQFH#EHWZHHQ#,/PD[#DQG#,/PLQ/#ZKLFK#LV#UHSUHVHQWHG#E\#∆,#>
∆,# ,/PD[#0,/PLQ# 9287×WRSHQ2/ +9,109287,×WRQ2/111111111111111111111111111111111111111111111111111111111111111111111111111111(TXDWLRQ#4
11
R1221N
ZKHUHLQ#7 42IRVF WRQ.WRII
GXW\#+(, WRQ27×433 WRQ×IRVF×433
WRSHQ≤WRII
,Q#(TXDWLRQ#4/#9287×WRSHQ2/#DQG#+9,109287,×WRQ2/#DUH#UHVSHFWLYHO\#VKRZ#WKH#FKDQJH#RI#WKH#FXUUHQW#DW#21/#DQG#WKH
FKDQJH#RI#WKH#FXUUHQW#DW#2))1
:KHQ#WKH#RXWSXW#FXUUHQW#+,287,#LV#UHODWLYHO\#VPDOO/#WRSHQ?WRII#DV#LOOXVWUDWHG#LQ#WKH#DERYH#GLDJUDP1#,Q#WKLV#FDVH/#WKH
HQHUJ\#LV#FKDUJHG#LQ#WKH#LQGXFWRU#GXULQJ#WKH#WLPH#SHULRG#RI#WRQ#DQG#LV#GLVFKDUJHG#LQ#LWV#HQWLUHO\#GXULQJ#WKH#WLPH#SHULRG
RI#WRII/#WKHUHIRUH#,/PLQ#EHFRPHV#WR#]HUR#+,/PLQ 3,1#:KHQ#,287#LV#JUDGXDOO\#LQFUHDVHG/#HYHQWXDOO\/#WRSHQ#EHFRPHV#WR
WRII#+WRSHQ# #WRII,/#DQG#ZKHQ#,287#LV#IXUWKHU#LQFUHDVHG/#,/PLQ#EHFRPHV#ODUJHU#WKDQ#]HUR#+,/PLQ!3,1#7KH#IRUPHU#PRGH#LV
UHIHUUHG#WR#DV#WKH#GLVFRQWLQXRXV#PRGH#DQG#WKH#ODWWHU#PRGH#LV#UHIHUUHG#WR#DV#FRQWLQXRXV#PRGH1
,Q#WKH#FRQWLQXRXV#PRGH/#ZKHQ#(TXDWLRQ#4#LV#VROYHG#IRU#WRQ#DQG#DVVXPHG#WKDW#WKH#VROXWLRQ#LV#WRQF/
WRQF# 7×9,129287 1111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111 (TXDWLRQ#5
:KHQ#WRQ?WRQF/#WKH#PRGH#LV#WKH#GLVFRQWLQXRXV#PRGH/#DQG#ZKHQ#WRQ# #WRQF/#WKH#PRGH#LV#WKH#FRQWLQXRXV#PRGH1
OUTPUT CURRENT AND SELECTION OF EXTERNAL COMPONENTS
:KHQ#/[7U#LV#21=
+:KHUHLQ/#5LSSOH#&XUUHQW#303#YDOXH#LV#GHVFULEHG#DV#,53/#21#UHVLVWDQFH#RI#/;7U#LV#GHVFULEHG#DV#5S#WKH#GLUHFW#FXUUHQW
RI#WKH#LQGXFWRU#LV#GHVFULEHG#DV#5/1,
9,1 9287.+53#.5/,×,287./×,532WRQ 11111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111 (TXDWLRQ#6
:KHQ#/[7U#LV#2))=
/×,532#WRII# 9).9287.5/×,287 111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111 (TXDWLRQ#7
3XW#(TXDWLRQ#7#WR#(TXDWLRQ#6#DQG#VROYH#IRU#21#GXW\/#WRQ2+WRII.WRQ, '21/
'21 +9287.9).5/×,287,2+9,1.9)05S×,287, 11111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111 (TXDWLRQ#8
5LSSOH#&XUUHQW#LV#DV#IROORZV>
,53 +9,109287053×,28705/×,287,×'212I2/#111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111 (TXDWLRQ#9
ZKHUHLQ/#SHDN#FXUUHQW#WKDW#IORZV#WKURXJK#//#/[7U/#DQG#6'#LV#DV#IROORZV>
,/PD[ ,287.,5325111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111 (TXDWLRQ#:
12
R1221N
&RQVLGHU#,/PD[/#FRQGLWLRQ#RI#LQSXW#DQG#RXWSXW#DQG#VHOHFW#H[WHUQDO#FRPSRQHQWV1
★ 7KH#DERYH#H[SODQDWLRQ#LV#GLUHFWHG#WR#WKH#FDOFXODWLRQ#LQ#DQ#LGHDO#FDVH#LQ#FRQWLQXRXV#PRGH1
External Components
1. Inductor
6HOHFW#DQ#LQGXFWRU#WKDW#SHDN#FXUUHQW#GRHV#QRW#H[FHHG#,/PD[1#,I#ODUJHU#FXUUHQW#WKDQ#DOORZDEOH#FXUUHQW#IORZV/#PDJ0
QHWLF#VDWXUDWLRQ#RFFXUV#DQG#PDNH#WUDQVIRUP#HIILFLHQF\#ZRUVH1
:KHQ#WKH#ORDG#FXUUHQW#LV#VDPH/#WKH#VPDOOHU#YDOXH#RI#//#WKH#ODUJHU#WKH#ULSSOH#FXUUHQW1
3URYLGHG#WKDW#WKH#DOORZDEOH#FXUUHQW#LV#ODUJH#LQ#WKDW#FDVH#DQG#'&#FXUUHQW#LV#VPDOO/#WKHUHIRUH/#IRU#ODUJH#RXWSXW#FXUUHQW/
HIILFLHQF\#LV#EHWWHU#WKDQ#XVLQJ#DQ#LQGXFWRU#ZLWK#D#ODUJH#YDOXH#RI#/#DQG#YLFH#YHUVD/
2
Diode
8VH#D#GLRGH#ZLWK#ORZ#9)#+6FKRWWN\#W\SH#LV#UHFRPPHQGHG1,#DQG#KLJK#VZLWFKLQJ#VSHHG1
5HYHUVH#YROWDJH#UDWLQJ#VKRXOG#EH#PRUH#WKDQ#9,1#DQG#FXUUHQW#UDWLQJ#VKRXOG#EH#HTXDO#RU#PRUH#WKDQ#,/PD[1
61 &DSDFLtRU
$V#IRU#&,1/#XVH#D#FDSDFLWRU#ZLWK#ORZ#(65#+(TXLYDOHQW#6HULHV#5HVLVWDQFH,#DQG#D#FDSDFLW\#RI#DW#OHDVW#43—)#IRU#VWDEOH
RSHUDWLRQ1#&287#FDQ#UHGXFH#ULSSOH#RI#2XWSXW#9ROWDJH/#WKHUHIRUH#7:#WR#433—)#WDQWDOXP#W\SH#LV#UHFRPPHQGHG1
4. Lx Transistor
3FK#3RZHU#026#)(7#LV#UHTXLUHG#IRU#WKLV#,&1
,WV#EUHDNGRZQ#YROWDJH#EHWZHHQ#JDWH#DQG#VRXUFH#VKRXOG#EH#D#IHZ#YROW#KLJKHU#WKDQ#,QSXW#9ROWDJH1
,Q#WKH#FDVH#RI#,QSXW#9ROWDJH#LV#ORZ/#WR#WXUQ#RQ#026#)(7#FRPSOHWHO\/#VHOHFW#D#026#)(7#ZLWK#ORZ#WKUHVKROG#YROWDJH1
,I#D#ODUJH#ORDG#FXUUHQW#LV#QHFHVVDU\#IRU#\RXU#DSSOLFDWLRQ#DQG#LPSRUWDQW/#FKRRVH#D#026#)(7#ZLWK#ORZ#21#UHVLVWDQFH
IRU#JRRG#HIILFLHQF\1
,I#D#VPDOO#ORDG#FXUUHQW#LV#PDLQO\#QHFHVVDU\#IRU#\RXU#DSSOLFDWLRQ/#FKRRVH#D#026#)(7#ZLWK#ORZ#JDWH#FDSDFLW\#IRU#JRRG
HIILFLHQF\1
0D[LPXP#FRQWLQXRXV#GUDLQ#FXUUHQW#RI#026#)(7#VKRXOG#EH#ODUJHU#WKDQ#SHDN#FXUUHQW/#,/PD[1
13
R1221N
TYPICAL CHARACTERISTCS
1) Output Voltage vs. Output Current
R1221N15XH
L=27µH
1.520
1.515
1.510
1.505
1.500
1.495
1.490
1.485
1.480
13.2V
8V
5V
2.3V
1E-05 0.0001 0.001
0.01
0.1
1
Output Current IOUT (A)
2) Efficiency vs. Output Current
CD104-27µH
Si3443DV
CD104-27µH
Si3443DV
R1221N33AA(VIN=12V)
R1221N33AA(VIN=4.5V)
100
100
90
80
70
60
50
90
80
70
60
50
40
30
20
40
30
20
10
0
0.1
10
0
0.1
1
10
100
1000
1
10
100
1000
Output Current IOUT (mA)
Output Current IOUT (mA)
CD104-27µH
CD104-27µH
Si3443DV
Si3443DV
R1221N33AC(VIN=4.5V)
R1221N33AB(VIN=12V)
100
80
100
80
60
60
40
20
0
40
20
0
0.1
1
10
100
1000
0.1
1
10
100
1000
Output Current IOUT (mA)
Output Current IOUT (mA)
14
R1221N
CD104-27µH
Si3443DV
CD104-27µH
Si3443DV
R1221N33AC(VIN=4.5V)
R1221N33AC(VIN=12V)
100
90
80
70
60
50
100
90
80
70
60
50
40
30
20
40
30
20
10
0
0.1
10
0
0.1
1
10
100
1000
1
10
100
1000
Output Current IOUT (mA)
Output Current IOUT (mA)
CD104-27µH
CD104-27µH
Si3443DV
Si3443DV
R1221N50XA(VIN=12V)
R1221N50XA(VIN=6.0V)
100
80
100
80
60
60
40
20
0
40
20
0
0.1
1
10
100
1000
0.1
1
10
100
1000
Output Current IOUT (mA)
Output Current IOUT (mA)
CD104-27µH
CD104-27µH
Si3443DV
Si3443DV
R1221N50XB(VIN=6.0V)
R1221N50XB(VIN=12V)
100
80
100
80
60
60
40
20
0
40
20
0
0.1
1
10
100
1000
0.1
1
10
100
1000
Output Current IOUT (mA)
Output Current IOUT (mA)
15
R1221N
CD104-27µH
CD104-27µH
Si3443DV
Si3443DV
R1221N50XC(VIN=12V)
R1221N50XC(VIN=6.0V)
100
80
100
80
60
60
40
20
0
40
20
0
0.1
1
10
100
1000
0.1
1
10
100
1000
Outpur Current IOUT (mA)
Outpur Current IOUT (mA)
3) Ripple Voltage vs. Output Current
L=27µH
L=27µH
R1221N33AA
C=47µF(Ta)
C=47µF(Ta)
R1221N33AA
200
200
180
180
160
140
120
100
V
V
V
IN=6V
IN=8V
IN=12V
V
V
V
IN=4.5V
160
140
120
100
IN=8V
IN=12V
80
60
80
60
40
20
0
40
20
0
1
10
100
1000
1
10
100
1000
Output Current IOUT (mA)
Output Current IOUT (mA)
L=27µH
L=27µH
R1221N33AB
C=47µF(Ta)
C=47µF(Ta)
R1221N50XB
200
180
160
140
120
100
200
180
160
140
120
100
V
V
V
IN=4.5V
IN=8V
VIN=6V
VIN=8V
VIN=12V
IN=12V
80
60
80
60
40
20
0
40
20
0
1
10
100
1000
1
10
100
1000
Output Current IOUT (mA)
Output Current IOUT (mA)
16
R1221N
L=27µH
C=47µF(Ta)
L=27µH
C=47µF(Ta)
R1221N50XC
R1221N33AC
200
180
160
140
120
100
200
180
160
140
120
100
V
V
V
IN=6V
IN=8V
IN=12V
V
V
V
IN=4.5V
IN=8V
IN=12V
80
60
80
60
40
20
0
40
20
0
1
10
100
1000
1
10
100
1000
Output Current IOUT (mA)
Output Current IOUT (mA)
4) Oscillator Frequency vs. Input Voltage
R1221N15XB
R1221N15XA
L=27µH
L=27µH
600
600
500
400
300
200
100
0
500
400
300
200
100
0
0
5
10
15
0
5
10
15
Input Voltage VIN (V)
Input Voltage VIN (V)
5) Output Voltage vs. Input Voltage
R1221N15XB
R1221N15XA
L=27µH
L=27µH
1.53
1.53
1.52
1.51
1.50
1.49
1.48
1.47
1.52
1.51
1.50
1.49
1.48
1.47
0
5
10
15
0
5
10
15
Input Voltage VIN (V)
Input Voltage VIN (V)
17
R1221N
L=27µH
L=27µH
R1221N33AB
R1221N33AA
3.36
3.34
3.36
3.34
3.32
3.30
3.28
3.32
3.30
3.28
3.26
3.24
3.26
3.24
0
5
10
15
0
5
10
15
Input Voltage VIN (V)
Input Voltage VIN (V)
6) Output Voltage vs. Temperature
L=27µH
IN=2.7V
R1221N33AH
L=27µH
V
R1221N15XB
3.31
1.51
1.50
1.49
1.48
1.47
3.30
3.29
3.28
3.27
-50
0
50
100
-50
0
50
100
Temperature Topt (°C)
Temperature Topt (°C)
7) Detector Threshold vs. Temperature
R1221N25XA(VD=2.0V)
R1221N15XB(VD=1.2V)
VIN=6V
VIN=6V
2.01
1.22
1.21
2.00
1.20
1.19
1.18
1.99
1.98
1.97
-50
50
Temperature Topt (°C)
100
0
-50
50
Temperature Topt (°C)
100
0
18
R1221N
R1221N33AB(VD=3.0V)
VIN=6V
3.06
3.04
3.02
3.00
2.98
2.96
2.94
-50
50
Temperature Topt (°C)
100
0
8) Oscillator Frequency vs. Temperature
L=27µH
VIN=3.7V
L=27µH
R1221N33AB
R1221N25XA
VIN=4.5V
600
360
340
320
300
280
550
500
450
400
260
240
-50
50
100
-50
50
Temperature Topt (°C)
100
0
0
Temperature Topt (°C)
9) Supply Current vs. Temperature
R1221N33AH
R1221N33AG
135
100
90
80
70
60
50
130
125
120
VIN=15V
VIN=13.2V
VIN=8V
115
110
V
V
V
IN=15V
IN=13.2V
IN=8V
105
100
95
90
-50
50
Temperature Topt (°C)
100
0
-50
50
Temperature Topt (°C)
100
0
19
R1221N
10) Soft-start Time vs. Temperature
L=27µH
IN=4.5V
L=27µH
VIN=3.7V
R1221N33AB
V
R1221N25XA
10
12
10
8
8
6
4
2
0
6
4
2
-50
50
100
-50
50
Temperature Topt (°C)
100
0
0
Temperature Topt (°C)
11) Delay Time for Latch-type Protection vs. Temperature
R1221N33AB
R1221N25XA
VIN=4.5V
VIN=3.7V
4.0
4.0
3.5
3.0
3.5
3.0
2.5
2.0
1.5
1.0
0.5
0.0
2.5
2.0
1.5
1.0
0.5
0.0
-50
50
100
-50
50
Temperature Topt (°C)
100
0
0
Temperature Topt (°C)
12) Delay Time for Reset-type Protection vs. Temperature
R1221N33AH
R1221N33AG
VIN=4.5V
VIN=4.5V
5
5
4
3
2
1
0
4
3
2
1
0
-50
-50
50
Temperature Topt (°C)
100
0
50
Temperature Topt (°C)
100
0
20
R1221N
13) VD Output Delay Time vs. Temperature
R1221N33AB
R1221N25XA
V
IN=8.0V
V
IN=8.0V
6
6
5
4
3
2
5
4
3
2
1
0
1
0
-50
50
Temperature Topt (°C)
100
-50
50
Temperature Topt (°C)
100
0
0
14) EXT"H" Output Current vs. Temperature
15) EXT "L" Output Current vs. Temperature
R1221N33AB
R1221N33AB
16
30
14
12
25
20
15
10
10
8
6
4
5
0
2
0
-50
50
Temperature Topt (°C)
100
0
-50
50
Temperature Topt (°C)
100
0
16) VDOUT "L" Output Current vs. Temperature
R1221N33AD
1.6
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0.0
-50
50
Temperature Topt (°C)
100
0
21
R1221N
17) Load Transient Response
V
IN=5V
VIN=5V
R1221N33AA
L=27µH
R1221N33AA
L=27µH
3.6
3.4
3.5
3.4
3.2
3
3.3
3.2
3.1
3
500
500
2.8
2.6
2.9
2.8
2.7
2.6
0.1
0.001
0.1
2.4
0
0.05
0.1
0
0.0005
Time (sec)
Time (sec)
V
IN=5V
VIN=5V
R1221N33AB
L=27µH
R1221N33AB
L=27µH
3.4
3.6
3.3
3.2
3.5
3.4
3.3
2
3.1
3
500
500
3.1
3
2.9
2.8
2.7
2.6
2.9
2.8
2.7
2.6
2.5
2.4
0.1
0.1
0.1
0.001
0
0.05
0
0.0005
Time (sec)
Time (sec)
V
IN=5V
VIN=5V
R1221N33AC
L=27µH
L=27µH
R1221N33AC
3.4
3.6
3.3
3.2
3.5
3.4
3.1
3
3.3
2
500
500
2.9
2.8
2.7
2.6
3.1
3
2.9
2.8
2.5
2.4
2.7
2.6
0.1
0.001
0.1
0.1
0
0
0.0005
0.05
Time (sec)
Time (sec)
22
R1221N
V
IN=5V
V
IN=5V
R1221N33AD
L=27µH
L=27µH
R1221N33AD
3.4
3.6
3.3
3.2
3.5
3.4
3.1
3
3.3
2
500
500
2.9
2.8
2.7
2.6
3.1
3
2.9
2.8
2.7
2.6
2.5
2.4
0.1
0.1
0.1
0.001
0
0
0.05
0.0005
Time (sec)
Time (sec)
18) Turn-on Waveform
R1221N33AA(VIN=10V,IOUT=0mA)
L=27µH
R1221N33AA(VIN=5V,IOUT=0mA)
L=27µH
3.5
3
3.5
3
2.5
2.5
2
2
1.5
1.5
1
0.5
0
1
0.5
0
10
5
-0.5
-1
-0.5
-1
-1.5
-2
-1.5
-2
-2.5
-3
-2.5
-3
0
0
-3.5
-3.5
-0.01
0
0.01
-0.01
0
0.01
0.02
0.02
Time (sec)
Time (sec)
R1221N33AB(VIN=10V,IOUT=0mA)
L=27µH
R1221N33AB(VIN=5V,IOUT=0mA)
L=27µH
3.5
3
3.5
3
2.5
2.5
2
2
1.5
1.5
1
0.5
0
1
0.5
0
10
5
-0.5
-1
-0.5
-1
-1.5
-2
-1.5
-2
-2.5
-3
-2.5
-3
0
0
-3.5
-3.5
-0.01
0
0.01
-0.01
0
0.01
0.02
0.02
Time (sec)
Time (sec)
23
R1221N
R1221N33AA(VIN=10V,IOUT=100mA)
L=27µH
R1221N33AA(VIN=5V,IOUT=100mA)
L=27µH
3.5
3
3.5
3
2.5
2.5
2
2
1.5
1.5
1
0.5
0
1
0.5
0
10
5
-0.5
-1
-0.5
-1
-1.5
-2
-1.5
-2
-2.5
-3
-2.5
-3
0
0
-3.5
-3.5
-0.01
0
0.01
-0.01
0
0.01
0.02
0.02
Time (sec)
Time (sec)
R1221N33AB(VIN=5V,IOUT=100mA)
L=27µH
R1221N33AB(VIN=10V,IOUT=100mA)
L=27µH
3.5
3
3.5
3
2.5
2.5
2
2
1.5
1.5
1
0.5
0
1
0.5
0
5
10
-0.5
-1
-0.5
-1
-1.5
-2
-1.5
-2
-2.5
-3
-2.5
-3
0
0
-3.5
-3.5
-0.01
0
0.01
-0.01
0
0.01
0.02
0.02
Time (sec)
Time (sec)
24
相关型号:
R1221N38AA-TR-FA
Switching Controller, 0.025A, 360kHz Switching Freq-Max, CMOS, PDSO6, SOT-23, 6 PIN
RICOH
©2020 ICPDF网 联系我们和版权申明