NO. EA-058-0006
/2:#12,6(#483P$#/'2
5(*8/$725
5445 4 1#6(5,(6
$33/,&$7,21#0$18$/
LOW NOISE 150mA LDO REGULATOR
544541#6(5,(6
1
OUTLINE
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FEATURES
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APPLICATIONS
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R1121N
2
BLOCK DIAGRAM
R1121NXX1A R1121NXX1B
Vref
Current Limit
V
DD
31
24
V
OUT
GNDCE
Vref
Current Limit
V
DD
31
24
V
OUT
GNDCE
SELECTION GUIDE
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Code Contents
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R1121N
3
PIN CONFIGURATION
SOT-23-5
54
NC CE
(mark side)
123
V
OUT
GND V
DD
PIN DESCRIPTION
Pin No. Symbol Description
49287 2XWSXW#SLQ
5*1' *URXQG#3LQ
69'' ,QSXW#3LQ
7&( #RU#&( &KLS#(QDEOH#3LQ
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ABSOLUTE MAXIMUM RATINGS
Symbol Item Rating Unit
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9287 2XWSXW#9R O W D J H 0316a#9,1.316 9
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R1121N
4
ELECTRICAL CHARACTERISTICS
R1121NXX1A 7R S W # #58°&
Symbol Item Conditions MIN. TYP. MAX. Unit
9287 2XWSXW#9R O W D J H 9,1# #6HW#9287.49
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9&(+ CE #,QSXW#9R O W D J H #´+µ 418 9,1 9
9&(/ CE #,QSXW#9R O W D J H #´/µ 3 3158 9
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R1121N
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R1121NXX1B 7R S W 58°&
Symbol Item Conditions MIN. TYP. MAX. Unit
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R1121N
6
ELECTRICAL CHARACTERISTICS by OUTPUT VOLTAGE
7R S W # #58°&
Output Current
IOUT (mA)
Output Voltage
VOUT (V) Conditions MIN.
418##9287##41: 433
41;##9287##813
9,1#0#9287# #4139
483
7R S W # #58°&
Dropout Voltage
VDIF (V)
Output Voltage
VOUT (V) Conditions MIN. TYP. MAX.
418 318
419 317
41: 316
41;##9287##41< 3193 4173
513##9287##517 3168 31:3
518##9287##51: 3157 3168
51;##9287##616 3153 3163
617##9287##813
,287# #433P$
314: 3159
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R1121N
7
OPERATION R1121NXX1A R1121NXX1B
V
DD
31
24
V
OUT
GND
R2
R1
CE Current Limit
Vref
V
DD
31
24
V
OUT
GND
R2
R1
CE Current Limit
Vref
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LV#FRPSDUHG#ZLWK#D#UHIHUHQFH#YROWDJH#E\#(UURU#$PSOLILHU/#VR#WKDW#D#FRQVWDQW#YROWDJH#LV#RXWSXW1
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R1121N
8
TEST CIRCUITS
R1121Nxx1B Series
V
DD
1
3
2
4
V
OUT
I
OUT
IN OUT
GND
CE
0.1µF
2.2µF
Standard test Circuit
R1121Nxx1B Series
V
DD
1
3
2
4
V
OUT
I
SS
IN OUT
GND
CE
0.1µF
2.2µF
Supply current Test
Circuit
Fig.1 Standard test Circuit Fig.2 Supply Current Test Circuit
R1121Nxx1B Series
V
DD
1
3
P.G 2
4
V
OUT
I
OUT
IN OUT
GND
CE
Ripple Rejection, Line
Transient Response Test Circuit
R1121Nxx1B Series
V
DD
1
3
2
4
V
OUT
IN OUT
GND I1 I2
CE
1µF
Load Transient Response
Test Circuit
Fig.3 Ripple Rejection, Line Tr ansient Response
Test Circuit
Fig.4 Load Transient Response Test Circuit
R1121N
9
TYPICAL CHARACTERISTICS
1) Output Voltage vs. Output Current
R1121N181B R1121N301B
2.0
3.8V 2.8V
2.3V
VIN = 2.1V
Topt = 25°C
1.8
1.6
1.0
0.8
0.6
0.4
0.2
1.4
1.2
0.0
Output Current IOUT (mA)
0 200 300 400 500100
Output V oltage VOUT (V)
3.5 5.0V
4.0V
3.5V
V
IN
= 3.3V
Topt = 25°C
2.5
1.5
1.0
0.5
2.0
3.0
0.0
Output Current I
OUT
(mA)
0 200 300 400 500100
Output V oltage V
OUT
(V)
R1121N401B R1121N501B
5.0
6.0V
Topt = 25°C
5.0V
4.5V
V
IN
= 4.3V
4.5
4.0
2.5
2.0
1.5
1.0
0.5
3.5
3.0
0.0
Output Current I
OUT
(mA)
0 200 300 400 500100
Output V oltage V
OUT
(V)
6.0
7.0V
Topt = 25°C
6.0V
5.5V
VIN = 5.3V
5.0
3.0
2.0
1.0
4.0
0.0
Output Current IOUT (mA)
0 200 300 400 500100
Output V oltage VOUT (V)
2) Output Voltage vs. Input Voltage
R1121N181B R1121N301B
2.0 Topt = 25°C
I
OUT
= 1mA
30mA
50mA
1.9
1.8
1.7
1.6
1.5
1.4
1.2
1.3
Input V oltage V
IN
(V)
1.0 4.0 5.0 6.0 7.0 8.02.0 3.0
Output V oltage V
OUT
(V)
3.1
3.0
2.9
2.8
2.7
2.5
2.6
Input V oltage V
IN
(V)
2.0 4.0 5.0 6.0 7.0 8.03.0
Output V oltage V
OUT
(V)
Topt = 25°C
30mA
50mA
I
OUT
=1mA
R1121N
10
R1121N401B R1121N501B
4.5
I
OUT
= 1mA
30mA
50mA
Topt = 25°C
4.0
3.5
3.0
2.5
Input V oltage V
IN
(V)
2.0 4.0 5.0 6.0 8.07.03.0
OUtput V oltage V
OUT
(V)
5.5
I
OUT
= 1mA
30mA
50mA
Topt = 25°C
5.0
4.0
3.5
3.0
4.5
2.5
Input V oltage V
IN
(V)
2.0 4.0 5.0 6.0 8.07.03.0
Output V oltage V
OUT
(V)
3) Dropout Voltage vs. Output Current
R1121N181B R1121N301B
1.20
Topt = 85°C
25°C
-40°C
1.00
0.80
0.60
0.40
0.20
0.00
Output Current I
OUT
(mA)
0 50 100 150
Dropout V oltage V
DIF
(V)
0.40
Topt = 85°C
25°C
-40°C
0.35
0.30
0.20
0.15
0.10
0.05
0.25
0.00
Output Current I
OUT
(mA)
0 50 100 150
Dropout V oltage V
DIF
(V)
R1121N401B R1121N501B
0.40
Topt = 85°C
25°C
-40°C
0.35
0.30
0.25
0.20
0.15
0.00
0.05
0.10
Output Current I
OUT
(mA)
0 50 100 150
Dropout V oltage V
DIF
(V)
0.40
Topt = 85°C
25°C
-40°C
0.35
0.30
0.25
0.20
0.15
0.00
0.05
0.10
Output Current IOUT (mA)
0 50 100 150
Dropout V oltage VDIF (V)
R1121N
11
4) Output Voltage vs. Temperature
R1121N181B R1121N301B
1.90
V
IN
= 2.8V
I
OUT
= 30mA
1.88
1.86
1.80
1.78
1.76
1.74
1.72
1.84
1.82
1.70
Temperature Topt (°C)
-50 0 25 50 10075-25
Output V oltage V
OUT
(V)
3.10 IOUT = 30mA
VIN = 4.0V
3.08
3.06
3.00
2.98
2.96
2.94
2.92
3.04
3.02
2.90
Temperature Topt (°C)
-50 0 25 50 10075-25
Output V oltage VOUT (V)
R1121N401B R1121N501B
4.10 I
OUT
= 30mA
V
IN
= 5.0V
4.08
4.06
4.00
3.98
3.96
3.94
3.92
4.04
4.02
3.90
Temperature Topt (°C)
-50 0 25 50 10075-25
Output V oltage V
OUT
(V)
5.10 I
OUT
= 30mA
V
IN
= 6.0V
5.08
5.06
5.00
4.98
4.96
4.94
4.92
5.04
5.02
4.90
Tempareture Topt (°C)
-50 0 25 50 10075-25
Output V oltage V
OUT
(V)
5) Supply Current vs. Input Voltage
R1121N181B R1121N301B
60 Topt = 25°C
50
40
30
20
0
10
Input V oltage V
IN
(V)
1.0 2.0 4.0 5.0 6.0 7.0 8.03.0
Supply Current I
SS
(µA)
60 Topt = 25°C
50
40
30
20
0
10
Input V oltage V
IN
(V)
1.0 2.0 4.0 5.0 6.0 7.0 8.03.0
Supply Current I
SS
(µA)
R1121N
12
R1121N401B R1121N501B
60 Topt = 25°C
50
40
30
20
10
0
Input V oltage V
IN
(V)
1.0 4.0 5.0 6.0 7.0 8.02.0 3.0
Supply Current I
SS
(µA)
60 Topt = 25°C
50
40
30
20
10
0
Input V oltage V
IN
(V)
1.0 4.0 5.0 6.0 7.0 8.02.0 3.0
Supply Current I
SS
(µA)
6) Supply Current vs. Temperature
R1121N181B R1121N301B
50 V
IN
= 2.8V
45
40
35
30
20
25
Temperature Topt (°C)
-50 50 1000
Supply Current I
SS
(µA)
50 V
IN
= 4.0V
45
40
35
30
20
25
Temperature Topt (°C)
-50 50 1000
Supply Current I
SS
(µA)
R1121N401B R1121N501B
50 V
IN
= 5.0V
45
40
35
30
20
25
Temperature Topt (°C)
-50 50 1000
Supply Current I
SS
(µA)
50 V
IN
= 6.0V
45
40
35
30
20
25
Temperature Topt (°C)
-50 50 1000
Supply Current I
SS
(µA)
R1121N
13
7) Dropout Voltage vs. Set Output Voltage
R1121N××
××××
××1B
0.8
0.9
1.0
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0.01.0 2.0 3.0 4.0 5.0
I
OUT
= 150mA
I
OUT
= 100mA
I
OUT
= 50mA
I
OUT
= 30mA
I
OUT
= 10mA
Set Output V oltage Vreg (V)
Dropout V oltage V
DIF
(V)
Topt = 25°C
8) Ripple Rejection vs. Frequency
R1121N181B R1121N181B
80
70
60
50
40
30
20
10
00.1 1 10 100
I
OUT
= 1mA
I
OUT
= 30mA
I
OUT
= 50mA
Frequency f (kHz)
Ripple Rejection RR (dB)
V
IN
= 2.8V
DC
+ 0.5Vp-p
C
OUT
= tantal 1.0µF
80
70
60
50
40
30
20
10
00.1 1 10 100
IOUT= 1mA
IOUT = 30mA
IOUT = 50mA
Frequency f (kHz)
Ripple Rejection RR (dB)
VIN = 2.8VDC + 0.5Vp-p
COUT = tantal 2.2µF
R1121N301B R1121N301B
80
70
60
50
40
30
20
10
00.1 1 10 100
I
OUT
= 1mA
I
OUT
= 30mA
I
OUT
= 50mA
Frequency f (kHz)
Ripple Rejection RR (dB)
V
IN
= 4.0V
DC
+ 0.5Vp-p
C
OUT
= tantal 1.0µF
80
70
60
50
40
30
20
10
00.1 1 10 100
IOUT = 1mA
IOUT = 30mA
IOUT = 50mA
Frequency f (kHz)
Ripple Rejection RR (dB)
VIN = 4.0VDC + 0.5Vp-p
COUT = tantal 2.2µF
R1121N
14
R1121N401B R1121N401B
80
70
60
50
40
30
20
10
00.1 1 10 100
I
OUT
= 1mA
I
OUT
= 30mA
I
OUT
= 50mA
Frequency f (kHz)
Ripple Rejection RR (dB)
V
IN
= 5.0V
DC
+ 0.5Vp-p
C
OUT
= tantal 1.0µF
80
70
60
50
40
30
20
10
00.1 1 10 100
I
OUT
= 1mA
I
OUT
= 30mA
I
OUT
= 50mA
Frequency f (kHz)
Ripple Rejection RR (dB)
V
IN
= 5.0V
DC
+ 0.5Vp-p
C
OUT
= tantal 2.2µF
9) Ripple Rejection vs. Input Voltage (DC bias)
R1121N301B R1121N301B
80
70
60
50
40
30
20
10
03.1 3.2 3.3 3.4 3.5
f = 400Hz
f = 1kHz
f = 10kHz
Input V oltage V
IN
(V)
Ripple Rejection RR (dB)
I
OUT
= 1mA
C
OUT
= 2.2µF
80
70
60
50
40
30
20
10
03.1 3.2 3.3 3.4 3.5
f = 400Hz
f = 1kHz
f = 10kHz
Input V oltage VIN (V)
Ripple Rejection RR (dB)
IOUT = 10mA
COUT = 2.2µF
R1121N301B
80
70
60
50
40
30
20
10
03.1 3.2 3.3 3.4 3.5
f = 400Hz
f = 1kHz
f = 10kHz
Input V oltage V
IN
(V)
Ripple Rejection RR (dB)
I
OUT
= 50mA
C
OUT
= 2.2µF
R1121N
15
10) Line Transient Response R1121N301B
IOUT=30mA
tr=tf=5 µs
COUT=Tantalum 1.0µF
2.8
2.9
3.0
3.1
3.2
3.3
3.4
TIme t (µs)
OUtput V oltage VOUT (V)
Input V oltage VIN (V)
0 20 40 60 80 100 120 0
1
6
5
4
3
2
Input V oltage
Output V oltage
R1121N301B
I
OUT
=30mA
tr=tf=5 µs
C
OUT
=Tantalum 2.2µF
2.8
2.9
3.0
3.1
3.2
3.3
3.4
Time t (µs)
Output V oltage V
OUT
(V)
Input V oltage V
IN
(V)
0 20 40 60 80 100 120 0
1
6
5
4
3
2
Input V oltage
Output V oltage
R1121N301B
IOUT=30mA
tr=tf=5 µs
COUT=Tantalum 6.8µF
2.8
2.9
3.0
3.1
3.2
3.3
3.4
Time t (µs)
Output V oltage VOUT (V)
Input V oltage VIN (V)
0 20 40 60 80 100 1200
1
6
5
4
3
2
Input V oltage
Output V oltage
R1121N
16
11) Load Transient Response R1121N301B
V
IN
=4V
C
IN
=Tantalum 1µF
C
OUT
=Tantalum 1.0µF
2.8
2.9
3.0
3.1
3.2
3.3
3.4
Time t (µs)
Output V oltage V
OUT
(V)
Output Current I
OUT
(mA)
02468
10 12 14 16 18 20 -150
-100
150
100
50
0
-50
Output Current
Output V oltage
R1121N301B
V
IN
=4V
C
IN
=Tantalum 1µF
C
OUT
=Tantalum 2.2µF
2.8
2.9
3.0
3.1
3.2
3.3
3.4
Time t (µs)
Output V oltage V
OUT
(V)
Output Current I
OUT
(mA)
02468
10 12 14 16 18 20 -150
-100
150
100
50
0
-50
Output Current
Output V oltage
R1121N301B
V
IN
=4V
C
IN
=Tantalum 1µF
C
OUT
=Tantalum 6.8µF
2.8
2.9
3.0
3.1
3.2
3.3
3.4
Time t (µs)
Output V oltage V
OUT
(V)
Output Current I
OUT
(mA)
02468
10 12 14 16 18 20 -150
-100
150
100
50
0
-50
Output Current
Output V oltage
R1121N
17
TECHNICAL NOTES
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Vout
Iout
Vin
Vin
CE
GND ESR
Ceramic
Capacitor
Ceramic Capacitor
1µF
R1121N301B Spectrum
Analyzer
S.A.
4
32
1
Measuring Circuit for white noise ; R1121N301B
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R1121N301B R1121N301B
100.0
10.0
1.0
0.1
Output Current I
OUT
(mA)
0 10050 150
ESR ( )
Ceramic 1.0µF
100.0
10.0
1.0
0.1
Output Current I
OUT
(mA)
0 10050 150
ESR ( )
Ceramic 2.2µF
R1121N
18
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WR#ZRUN#FRUUHFWO\1
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TYPICAL APPLICATION
R1121NXX1A V
OUT
OUTIN V
DD
GND
CE
Cap.
Cap.
R1121Nxx1B V
OUT
OUTIN V
DD
GND
CE
Cap.
Cap.