R1221N20XC-TR-FA [RICOH]
Switching Controller, 360kHz Switching Freq-Max, CMOS, PDSO6, SOT-23, 6 PIN;
| 型号： | R1221N20XC-TR-FA |
| 厂家： | 
RICOH ELECTRONICS DEVICES DIVISION |
| 描述： | Switching Controller, 360kHz Switching Freq-Max, CMOS, PDSO6, SOT-23, 6 PIN 开关 光电二极管 |
| 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 |
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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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FEATURES
• :LGH#5DQJH#RI#,QSXW#9ROWDJH 111111111111111111111111111111111111111111111 5169#WR#46159
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• +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
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• 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
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D E F
Code
Contents
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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
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9287
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ABSOLUTE MAXIMUM RATING
Symbol
Item
Rating
48
Unit
9
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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
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R1221N
Symbol
Item
Conditions
9,1 99/#9&( 99/
MIN. TYP. MAX. Note* Unit
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6
R1221N
• R1221N***B (D,F,H) Output Voltage : Vo, Detector Threshold : VD
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Symbol
Item
Conditions
MIN. TYP. MAX. Note* Unit
9,1
2SHUDWLQJ#,QSXW#9ROWDJH
516
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9
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Symbol
Item
Conditions
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TEST CIRCUITS
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VEXT
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4
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TYPICAL APPLICATIONS AND APPLICATION HINTS
PMOS
L
VCC
EXT
VIN
V
OUT
SD1
C
OUT
R1
CE
CIN
Reset/
VDOUT
GND
CE CONTROL
CPU
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10
R1221N
✩
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OPERATION of step-down DC/DC converter and Output Current
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<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
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• Discontinuous Conduction Mode and Continuous Conduction Mode
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11
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
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
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