Step-down DC/DC Converter Controller
with Voltage Detector
545541#6(5,(6
OUTLINE
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FEATURES
•
:LGH#5DQJH#RI#,QSXW#9ROWDJH111111111111111111111111111111111111111111111
5169#WR#46159
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7ZR#FKRLFHV#RI#2VFLOODWRU#)UHTXHQF\11111111111111111111111111111111
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111111111111111111111111111111111111111111111111111111111111111111
7<3
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1111111111111111111111111111111111111111111111111111111111111111
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6HWWLQJ#2XWSXW#9ROWDJH
111111111111111111111111111111111111111111111111111111
6WHSZLVH#VHWWLQJ#ZLWK#D#VWHS#RI#3149#LQ#WKH#UDQJH#RI#4189
WR#8139
•
+LJK#$FFXUDF\#2XWSXW#9ROWDJH
11111111111111111111111111111111111111111
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WR#7189
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11111111111111111111
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1
R1221N
SELECTION GUIDE
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↑ ↑↑
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Code
D
6HWWLQJ#2XWSXW#9ROWDJH#+9
287
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Contents
PIN CONFIGURATION
SOT-23-6W
6
5
4
V
OUT
GND CE
(mark side)
EXT VD
OUT
V
IN
1
2
3
3
R1221N
PIN DESCRIPTION
Pin No.
4
5
6
7
8
9
Symbol
(;7
9'
287
9
,1
&(
*1'
9
287
Description
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9ROWDJH#'HWHFWRU#2XWSXW#3LQ#+2XWSXW#7\SH#>#1FK#2SHQ#'UDLQ,
3RZHU#6XSSO\#3LQ
&KLS#(QDEOH#3LQ
*URXQG#3LQ
3LQ#IRU#0RQLWRULQJ#2XWSXW#9ROWDJH
ABSOLUTE MAXIMUM RATING
Symbol
9
,1
9
(;7
9
&(
9'
287
9
287
,
(;7
3'
7RSW
7VWJ
Item
9
,1
#6XSSO\#9ROWDJH
(;7#3LQ#2XWSXW#9ROWDJH
&(#3LQ#,QSXW#9ROWDJH
9'
287
#3LQ#2XWSXW#9ROWDJH
9
287
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3RZHU#'LVVLSDWLRQ
2SHUDWLQJ#7HPSHUDWXUH#5DQJH
6WRUDJH#7HPSHUDWXUH#5DQJH
Rating
48
0316∼9
,1
.316
0316∼9
,1
.316
0316∼48
0316∼9
,1
.316
“58
583
073∼.;8
088∼.458
Unit
9
9
9
9
9
P$
P:
ƒ&
ƒ&
4