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10
External Components
1.
Inductor
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R1225N
11
TIMING CHART
Case 1. Set V
OUT
Voltage >2.1V (Set V
OUT
Voltage>UVLO Voltage)
V
IN
UVLO Voltage
UVLO Reset
CE Reset
V
OUT
Set Output Voltage
V
OUT
Set Output Voltage
V
OUT
Set Output Voltage
V
OUT
Set Output Voltage
Protection Circuit Delay Time
Protection Circuit Delay Time
Latch Protection
Latch Protection
Stable Operation
Stable Operation
Soft Start
CE
EXT
V
OUT
Soft Start
Soft Start
Stable Operation
Input Voltage
Rising Time
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DWLQJ
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R1225N
12
Case 2. Set V
OUT
Voltage
2.0V (Set V
OUT
Voltage < UVLO Voltage)
V
IN
UVLO Voltage
UVLO Voltage
UVLO Voltage
UVLO Reset
Reset with CE
V
OUT
Set Output Voltage
V
OUT
Set Output Voltage
Protection Circuit Delay Time
Latch Protection
Stable Operation
Stable Operation
Soft Start
CE
EXT
V
OUT
Soft Start
Soft Start
Stable Operation
Input Voltage
Rising Time
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R1225N
13
TEST CIRCUITS
A)
Output Voltage, Oscillator Frequency, CE "H" Input Voltage, CE "L" Input Voltage, Soft-start time
EXT
GND
V
OUT
V
IN
DLY
CE
C1
D1
+
-
L1
Oscilloscope
V
C2
+
-
PMOS
B)
Supply Current 1
C)
Standby Current
EXT
GND
V
OUT
V
IN
DLY
CE
A
EXT
GND
V
OUT
V
IN
DLY
CE
A
D)
EXT "H" Output Current
E)
EXT "L" Output Current
EXT
GND
V
OUT
V
IN
DLY
CE
A
EXT
GND
V
OUT
V
IN
DLY
CE
A
F)
DLY Switch Current
EXT
GND
V
OUT
V
IN
DLY
CE
A
R1225N
14
G) CE "H" Input Current, CE "L" Input Current
H)
Output Delay Time for Protection Circuit
EXT
GND
V
OUT
V
IN
DLY
CE
A
EXT
GND
V
OUT
V
IN
DLY
CE
C2
C3
+
-
Oscilloscope
3026 +$70 +LWDFKL
/ &'0& 6XPLGD +
6' 5%' 5RKP
&
) 7DQWDOXP 7\SH
& ) 7DQWDOXP 7\SH
& Q) &HUDPLF 7\SH
TYPICAL CHARACTERISTICS
$OPRVW DOO WKH FKDUDFWHULVWLFV RI 51 VHULHV DUH VDPH DV 51 6HULHV ([FHSW WKH IROORZLQJ FKDUDFWHULVWLFV
UHIHU WR WKH GDWDVKHHW RI 51 6HULHV
1)
Efficiency vs. Output Current
R1225N182A (V
IN
=3.3V) CDRH127-10uH
R1225N182A (V
IN
=5.0V) CDRH127-10uH
100
30
40
50
60
70
80
90
20
10
0
Output Current I
OUT
(mA)
Efficiency
(%)
0.1
1
10
100
1000
10000
Output Current I
OUT
(mA)
0.1
1
10
100
1000
10000
100
30
40
50
60
70
80
90
20
10
0
Efficiency
(%)
R1225N182B (V
IN
=3.3V) CDRH127-10uH
R1225N182B (V
IN
=5.0V) CDRH127-10uH
Output Current I
OUT
(mA)
0.1
1
10
100
1000
10000
100
30
40
50
60
70
80
90
20
10
0
Efficiency
(%)
Output Current I
OUT
(mA)
0.1
1
10
100
1000
10000
100
30
40
50
60
70
80
90
20
10
0
Efficiency
(%)
R1225N
15
R1225N182C (V
IN
=3.3V) CDRH127-10uH
R1225N182C (V
IN
=5.0V) CDRH127-10uH
Output Current I
OUT
(mA)
0.1
1
10
100
1000
10000
100
30
40
50
60
70
80
90
20
10
0
Efficiency
(%)
Output Current I
OUT
(mA)
0.1
1
10
100
1000
10000
100
30
40
50
60
70
80
90
20
10
0
Efficiency
(%)
R1225N182C (V
IN
=12V) CDRH127-10uH
R1225N182D (V
IN
=3.3V) CDRH127-10uH
Output Current I
OUT
(mA)
0.1
1
10
100
1000
10000
100
30
40
50
60
70
80
90
20
10
0
Efficiency
(%)
Output Current I
OUT
(mA)
0.1
1
10
100
1000
10000
100
30
40
50
60
70
80
90
20
10
0
Efficiency
(%)
R1225N182D (V
IN
=5.0V) CDRH127-10uH
R1225N182D (V
IN
=12V) CDRH127-10uH
Output Current I
OUT
(mA)
0.1
1
10
100
1000
10000
100
30
40
50
60
70
80
90
20
10
0
Efficiency
(%)
Output Current I
OUT
(mA)
0.1
1
10
100
1000
10000
100
30
40
50
60
70
80
90
20
10
0
Efficiency
(%)
R1225N
16
R1225N182J (V
IN
=3.3V) CDRH127-27uH
R1225N182J (V
IN
=5.0V) CDRH127-27uH
Output Current I
OUT
(mA)
0.1
1
10
100
1000
10000
100
30
40
50
60
70
80
90
20
10
0
Efficiency
(%)
Output Current I
OUT
(mA)
0.1
1
10
100
1000
10000
100
30
40
50
60
70
80
90
20
10
0
Efficiency
(%)
R1225N182K (V
IN
=3.3V) CDRH127-27uH
R1225N182K (V
IN
=5.0V) CDRH127-27uH
Output Current I
OUT
(mA)
0.1
1
10
100
1000
10000
100
30
40
50
60
70
80
90
20
10
0
Efficiency
(%)
Output Current I
OUT
(mA)
0.1
1
10
100
1000
10000
100
30
40
50
60
70
80
90
20
10
0
Efficiency
(%)
R1225N182K (V
IN
=12V) CDRH127-27uH
R1225N332A (V
IN
=4.8V) CDRH127-10Uh
Output Current I
OUT
(mA)
0.1
1
10
100
1000
10000
100
30
40
50
60
70
80
90
20
10
0
Efficiency
(%)
Output Current I
OUT
(mA)
0.1
1
10
100
1000
10000
100
30
40
50
60
70
80
90
20
10
0
Efficiency
(%)
R1225N
17
R1225N332A (V
IN
=7.0V) CDRH127-10uH
R1225N332B (V
IN
=4.8V) CDRH127-10uH
Output Current I
OUT
(mA)
0.1
1
10
100
1000
10000
100
30
40
50
60
70
80
90
20
10
0
Efficiency
(%)
Output Current I
OUT
(mA)
0.1
1
10
100
1000
10000
100
30
40
50
60
70
80
90
20
10
0
Efficiency
(%)
R1225N332B (V
IN
=7.0V) CDRH127-10uH
R1225N332C (V
IN
=4.8V) CDRH127-10uH
Output Current I
OUT
(mA)
0.1
1
10
100
1000
10000
100
30
40
50
60
70
80
90
20
10
0
Efficiency
(%)
Output Current I
OUT
(mA)
0.1
1
10
100
1000
10000
100
30
40
50
60
70
80
90
20
10
0
Efficiency
(%)
R1225N332C (V
IN
=12V) CDRH127-10uH
R1225N332C (V
IN
=15V) CDRH127-10uH
Output Current I
OUT
(mA)
0.1
1
10
100
1000
10000
100
30
40
50
60
70
80
90
20
10
0
Efficiency
(%)
Output Current I
OUT
(mA)
0.1
1
10
100
1000
10000
100
30
40
50
60
70
80
90
20
10
0
Efficiency
(%)
R1225N
18
R1225N332D (V
IN
=4.8V) CDRH127-10uH
R1225N332D (V
IN
=12V) CDRH127-10uH
Output Current I
OUT
(mA)
0.1
1
10
100
1000
10000
100
30
40
50
60
70
80
90
20
10
0
Efficiency
(%)
Output Current I
OUT
(mA)
0.1
1
10
100
1000
10000
100
30
40
50
60
70
80
90
20
10
0
Efficiency
(%)
R1225N332D (V
IN
=15V) CDRH127-10uH
R1225N332K (V
IN
=4.8V) CDRH127-27uH
Output Current I
OUT
(mA)
0.1
1
10
100
1000
10000
100
30
40
50
60
70
80
90
20
10
0
Efficiency
(%)
Output Current I
OUT
(mA)
0.1
1
10
100
1000
10000
100
30
40
50
60
70
80
90
20
10
0
Efficiency
(%)
R1225N332K (V
IN
=12V) CDRH127-27uH
R1225N332K (V
IN
=15V) CDRH127-27uH
Output Current I
OUT
(mA)
0.1
1
10
100
1000
10000
100
30
40
50
60
70
80
90
20
10
0
Efficiency
(%)
Output Current I
OUT
(mA)
0.1
1
10
100
1000
10000
100
30
40
50
60
70
80
90
20
10
0
Efficiency
(%)
R1225N
19
R1225N502A (V
IN
=6.5V) CDRH127-10uH
R1225N502A (V
IN
=10V) CDRH127-10uH
Output Current I
OUT
(mA)
0.1
1
10
100
1000
10000
100
30
40
50
60
70
80
90
20
10
0
Efficiency
(%)
Output Current I
OUT
(mA)
0.1
1
10
100
1000
10000
100
30
40
50
60
70
80
90
20
10
0
Efficiency
(%)
R1225N502B (V
IN
=6.5V) CDRH127-10uH
R1225N502B (V
IN
=10V) CDRH127-10uH
Output Current I
OUT
(mA)
0.1
1
10
100
1000
10000
100
30
40
50
60
70
80
90
20
10
0
Efficiency
(%)
Output Current I
OUT
(mA)
0.1
1
10
100
1000
10000
100
30
40
50
60
70
80
90
20
10
0
Efficiency
(%)
R1225N502C (V
IN
=6.5V) CDRH127-10uH
R1225N502C (V
IN
=12V) CDRH127-10uH
Output Current I
OUT
(mA)
0.1
1
10
100
1000
10000
100
30
40
50
60
70
80
90
20
10
0
Efficiency
(%)
Output Current I
OUT
(mA)
0.1
1
10
100
1000
10000
100
30
40
50
60
70
80
90
20
10
0
Efficiency
(%)
R1225N
20
R1225N502C (V
IN
=15V) CDRH127-10uH
R1225N502D (V
IN
=6.5V) CDRH127-10uH
Output Current I
OUT
(mA)
0.1
1
10
100
1000
10000
100
30
40
50
60
70
80
90
20
10
0
Efficiency
(%)
Output Current I
OUT
(mA)
0.1
1
10
100
1000
10000
100
30
40
50
60
70
80
90
20
10
0
Efficiency
(%)
R1225N502D (V
IN
=12V) CDRH127-10uH
R1225N502D (V
IN
=15V) CDRH127-10uH
Output Current I
OUT
(mA)
0.1
1
10
100
1000
10000
100
30
40
50
60
70
80
90
20
10
0
Efficiency
(%)
Output Current I
OUT
(mA)
0.1
1
10
100
1000
10000
100
30
40
50
60
70
80
90
20
10
0
Efficiency
(%)
R1225N502J (V
IN
=6.5V) CDRH127-27uH
R1225N502J (V
IN
=10V) CDRH127-27uH
Output Current I
OUT
(mA)
0.1
1
10
100
1000
10000
100
30
40
50
60
70
80
90
20
10
0
Efficiency
(%)
Output Current I
OUT
(mA)
0.1
1
10
100
1000
10000
100
30
40
50
60
70
80
90
20
10
0
Efficiency
(%)
R1225N
21
R1225N502K (V
IN
=6.5V) CDRH127-27uH
R1225N502K (V
IN
=12V) CDRH127-27uH
Output Current I
OUT
(mA)
0.1
1
10
100
1000
10000
100
30
40
50
60
70
80
90
20
10
0
Efficiency
(%)
Output Current I
OUT
(mA)
0.1
1
10
100
1000
10000
100
30
40
50
60
70
80
90
20
10
0
Efficiency
(%)
R1225N502K (V
IN
=15V) CDRH127-27uH
Output Current I
OUT
(mA)
0.1
1
10
100
1000
10000
100
30
40
50
60
70
80
90
20
10
0
Efficiency
(%)
2)
Ripple Voltage vs. Output Current
R1225N182A L=10uH
R1225N182B L=10uH
10
20
30
40
50
60
70
0
Output Current I
OUT
(mA)
Ripple Voltage Vrpp(mV)
0.1
1
10
100
1000
10000
V
IN
=3.3V
V
IN
=5.0V
10
20
30
40
50
60
70
0
Output Current I
OUT
(mA)
Ripple Voltage Vrpp(mV)
0.1
1
10
100
1000
10000
V
IN
=3.3V
V
IN
=5.0V
R1225N
22
R1225N182C L=10uH
R1225N182D L=10uH
10
20
30
40
50
60
70
0
Output Current I
OUT
(mA)
Ripple Voltage Vrpp(mV)
0.1
1
10
100
1000
10000
V
IN
= 3.3V
V
IN
= 5.0V
V
IN
=12.0V
10
20
30
40
50
60
70
0
Output Current I
OUT
(mA)
Ripple Voltage Vrpp(mV)
0.1
1
10
100
1000
10000
V
IN
= 3.3V
V
IN
= 5.0V
V
IN
=12.0V
R1225N182J L=27uH
R1225N182K L=27uH
10
20
30
40
50
60
70
0
Output Current I
OUT
(mA)
Ripple Voltage Vrpp(mV)
0.1
1
10
100
1000
10000
V
IN
=3.3V
V
IN
=5.0V
10
20
30
40
50
60
70
0
Output Current I
OUT
(mA)
Ripple Voltage Vrpp(mV)
0.1
1
10
100
1000
10000
V
IN
= 3.3V
V
IN
= 5.0V
V
IN
=12.0V
R1225N332A L=10uH
R1225N332B L=10uH
10
20
30
40
50
60
70
0
Output Current I
OUT
(mA)
Ripple Voltage Vrpp(mV)
0.1
1
10
100
1000
10000
V
IN
=4.8V
V
IN
=7.0V
10
20
30
40
50
60
70
0
Output Current I
OUT
(mA)
Ripple Voltage Vrpp(mV)
0.1
1
10
100
1000
10000
V
IN
=4.8V
V
IN
=7.0V
R1225N
23
R1225N332C L=10uH
R1225N332D L=10uH
10
20
30
40
50
60
70
0
Output Current I
OUT
(mA)
Ripple Voltage Vrpp(mV)
0.1
1
10
100
1000
10000
V
IN
= 4.8V
V
IN
=12.0V
V
IN
=15.0V
10
20
30
40
50
60
70
0
Output Current I
OUT
(mA)
Ripple Voltage Vrpp(mV)
0.1
1
10
100
1000
10000
V
IN
= 4.8V
V
IN
=12.0V
V
IN
=15.0V
R1225N332J L=27uH
R1225N332K L=27uH
10
20
30
40
50
60
70
0
Output Current I
OUT
(mA)
Ripple Voltage Vrpp(mV)
0.1
1
10
100
1000
10000
V
IN
=4.8V
V
IN
=7.0V
10
20
30
40
50
60
70
0
Output Current I
OUT
(mA)
Ripple Voltage Vrpp(mV)
0.1
1
10
100
1000
10000
V
IN
= 4.8V
V
IN
=12.0V
V
IN
=15.0V
R1225N502A L=10uH
R1225N502B L=10uH
10
20
30
40
50
60
70
0
Output Current I
OUT
(mA)
Ripple Voltage Vrpp(mV)
0.1
1
10
100
1000
10000
V
IN
= 6.5V
V
IN
=10.0V
10
20
30
40
50
60
70
0
Output Current I
OUT
(mA)
Ripple Voltage Vrpp(mV)
0.1
1
10
100
1000
10000
V
IN
= 6.5V
V
IN
=10.0V
R1225N
24
R1225N502C L=10uH
R1225N502D L=10uH
10
20
30
40
50
60
70
0
Output Current I
OUT
(mA)
Ripple Voltage Vrpp(mV)
0.1
1
10
100
1000
10000
V
IN
= 6.5V
V
IN
=12.0V
V
IN
=15.0V
10
20
30
40
50
60
70
0
Output Current I
OUT
(mA)
Ripple Voltage Vrpp(mV)
0.1
1
10
100
1000
10000
V
IN
= 6.5V
V
IN
=12.0V
V
IN
=15.0V
R1225N502J L=27uH
R1225N502K L=27uH
10
20
30
40
50
60
70
0
Output Current I
OUT
(mA)
Ripple Voltage Vrpp(mV)
0.1
1
10
100
1000
10000
V
IN
= 6.5V
V
IN
=10.0V
10
20
30
40
50
60
70
0
Output Current I
OUT
(mA)
Ripple Voltage Vrpp(mV)
0.1
1
10
100
1000
10000
V
IN
= 6.5V
V
IN
=12.0V
V
IN
=15.0V
3)
Input Voltage vs. Output Voltage
R1225N182A L=10uH
R1225N182B L=10uH
1.65
1.70
1.75
1.80
1.85
1.90
1.95
2.00
1.60
Input Voltage V
IN
(V)
Output Voltage V
OUT
(V)
0
5
10
15
20
1mA
500mA
1.65
1.70
1.75
1.80
1.85
1.90
1.95
2.00
1.60
Input Voltage V
IN
(V)
Output Voltage V
OUT
(V)
0
5
10
15
20
1mA
500mA
R1225N
25
R1225N182C L=10uH
R1225N182D L=10uH
1.65
1.70
1.75
1.80
1.85
1.90
1.95
2.00
1.60
Input Voltage V
IN
(V)
Output Voltage V
OUT
(V)
0
5
10
15
20
1mA
500mA
1.65
1.70
1.75
1.80
1.85
1.90
1.95
2.00
1.60
Input Voltage V
IN
(V)
Output Voltage V
OUT
(V)
0
5
10
15
20
1mA
500mA
R1225N182J L=27uH
R1225N182K L=27uH
1.65
1.70
1.75
1.80
1.85
1.90
1.95
2.00
1.60
Input Voltage V
IN
(V)
Output Voltage V
OUT
(V)
0
5
10
15
20
1mA
500mA
1.65
1.70
1.75
1.80
1.85
1.90
1.95
2.00
1.60
Input Voltage V
IN
(V)
Output Voltage V
OUT
(V)
0
5
10
15
20
1mA
500mA
R1225N332A L=10uH
R1225N332B L=10uH
3.38
3.36
3.34
3.32
3.30
3.28
3.26
3.24
3.22
3.40
3.20
Input Voltage V
IN
(V)
Output Voltage V
OUT
(V)
0
5
10
15
20
1mA
500mA
3.38
3.36
3.34
3.32
3.30
3.28
3.26
3.24
3.22
3.40
3.20
Input Voltage V
IN
(V)
Output Voltage V
OUT
(V)
0
5
10
15
20
1mA
500mA
R1225N
26
R1225N332C L=10uH
R1225N332D L=10uH
3.38
3.36
3.34
3.32
3.30
3.28
3.26
3.24
3.22
3.40
3.20
Input Voltage V
IN
(V)
Output Voltage V
OUT
(V)
0
5
10
15
20
1mA
500mA
3.38
3.36
3.34
3.32
3.30
3.28
3.26
3.24
3.22
3.40
3.20
Input Voltage V
IN
(V)
Output Voltage V
OUT
(V)
0
5
10
15
20
1mA
500mA
R1225N332J L=27uH
R1225N332K L=27uH
3.38
3.36
3.34
3.32
3.30
3.28
3.26
3.24
3.22
3.40
3.20
Input Voltage V
IN
(V)
Output Voltage V
OUT
(V)
0
5
10
15
20
1mA
500mA
3.38
3.36
3.34
3.32
3.30
3.28
3.26
3.24
3.22
3.40
3.20
Input Voltage V
IN
(V)
Output Voltage V
OUT
(V)
0
5
10
15
20
1mA
500mA
4)
Output Voltage vs. Output Current
R1225N182A L=10uH
R1225N182B L=10uH
1.830
1.810
1.790
1.770
1.850
1.750
Output Current I
OUT
(mA)
Output Voltage V
OUT
(V)
0.1
1
10
100
1000
10000
V
IN
=3.3V
V
IN
=5.0V
1.830
1.810
1.790
1.770
1.850
1.750
Output Current I
OUT
(mA)
Output Voltage V
OUT
(V)
0.1
1
10
100
1000
10000
V
IN
=3.3V
V
IN
=5.0V
R1225N
27
R1225N182C L=10uH
R1225N182D L=10uH
1.830
1.810
1.790
1.770
1.850
1.750
Output Current I
OUT
(mA)
Output Voltage V
OUT
(V)
0.1
1
10
100
1000
10000
V
IN
= 5.0V
V
IN
=12.0V
V
IN
= 3.3V
1.830
1.810
1.790
1.770
1.850
1.750
Output Current I
OUT
(mA)
Output Voltage V
OUT
(V)
0.1
1
10
100
1000
10000
V
IN
= 5.0V
V
IN
=12.0V
V
IN
= 3.3V
R1225N182J L=27uH
R1225N182K L=27uH
1.830
1.810
1.790
1.770
1.850
1.750
Output Current I
OUT
(mA)
Output Voltage V
OUT
(V)
0.1
1
10
100
1000
10000
V
IN
=5.0V
V
IN
=3.3V
1.830
1.810
1.790
1.770
1.850
1.750
Output Current I
OUT
(mA)
Output Voltage V
OUT
(V)
0.1
1
10
100
1000
10000
V
IN
= 5.0V
V
IN
=12.0V
V
IN
= 3.3V
R1225N332A L=10uH
R1225N332B L=10uH
3.38
3.36
3.34
3.32
3.30
3.28
3.26
3.24
3.22
3.40
3.20
Output Current I
OUT
(mA)
Output Voltage V
OUT
(V)
0.1
1
10
100
1000
10000
V
IN
=4.8V
V
IN
=7.0V
3.380
3.360
3.340
3.320
3.300
3.280
3.260
3.240
3.220
3.400
3.200
Output Current I
OUT
(mA)
Output Voltage V
OUT
(V)
0.1
1
10
100
1000
10000
V
IN
=4.8V
V
IN
=7.0V
R1225N
28
R1225N332C L=10uH
R1225N332D L=10uH
Output Current I
OUT
(mA)
0.1
1
10
100
1000
10000
3.380
3.360
3.340
3.320
3.300
3.280
3.260
3.240
3.220
3.400
3.200
Output Voltage V
OUT
(V)
V
IN
=12.0V
V
IN
=15.0V
V
IN
= 4.8V
Output Current I
OUT
(mA)
0.1
1
10
100
1000
10000
3.380
3.360
3.340
3.320
3.300
3.280
3.260
3.240
3.220
3.400
3.200
Output Voltage V
OUT
(V)
V
IN
=12.0V
V
IN
=15.0V
V
IN
= 4.8V
R1225N332J L=27uH
R1225N332K L=27uH
3.380
3.360
3.340
3.320
3.300
3.280
3.260
3.240
3.220
3.400
3.200
Output Current I
OUT
(mA)
Output Voltage V
OUT
(V)
0.1
1
10
100
1000
10000
V
IN
=4.8V
V
IN
=7.0V
Output Current I
OUT
(mA)
0.1
1
10
100
1000
10000
3.380
3.360
3.340
3.320
3.300
3.280
3.260
3.240
3.220
3.400
3.200
Output Voltage V
OUT
(V)
V
IN
=12.0V
V
IN
=15.0V
V
IN
= 4.8V
R1225N502A L=10uH
R1225N502B L=10uH
5.080
5.060
5.040
5.020
5.000
4.980
4.960
4.940
4.920
5.100
4.900
Output Current I
OUT
(mA)
Output Voltage V
OUT
(V)
0.1
1
10
100
1000
10000
V
IN
= 6.5V
V
IN
=10.0V
5.080
5.060
5.040
5.020
5.000
4.980
4.960
4.940
4.920
5.100
4.900
Output Current I
OUT
(mA)
Output Voltage V
OUT
(V)
0.1
1
10
100
1000
10000
V
IN
= 6.5V
V
IN
=10.0V
R1225N
29
R1225N502C L=10uH
R1225N502D L=10uH
Output Current I
OUT
(mA)
0.1
1
10
100
1000
10000
5.080
5.060
5.040
5.020
5.000
4.980
4.960
4.940
4.920
5.100
4.900
Output Voltage V
OUT
(V)
V
IN
=12.0V
V
IN
=15.0V
V
IN
= 6.5V
Output Current I
OUT
(mA)
0.1
1
10
100
1000
10000
5.080
5.060
5.040
5.020
5.000
4.980
4.960
4.940
4.920
5.100
4.900
Output Voltage V
OUT
(V)
V
IN
=12.0V
V
IN
=15.0V
V
IN
= 6.5V
R1225N502J L=27uH
R1225N502K L=27uH
5.080
5.060
5.040
5.020
5.000
4.980
4.960
4.940
4.920
5.100
4.900
Output Current I
OUT
(mA)
Output Voltage V
OUT
(V)
0.1
1
10
100
1000
10000
V
IN
= 6.5V
V
IN
=10.0V
Output Current I
OUT
(mA)
0.1
1
10
100
1000
10000
5.080
5.060
5.040
5.020
5.000
4.980
4.960
4.940
4.920
5.100
4.900
Output Voltage V
OUT
(V)
V
IN
=12.0V
V
IN
=15.0V
V
IN
= 6.5V
5)
Load Transient Response
R1225N332A L=10uH V
IN
=4.8V
R1225N332A L=10uH V
IN
=4.8V
Time(sec)
-0.0002 -0.0001 0.0000 0.0001 0.0002 0.0003 0.0004
3.40
3.30
3.20
3.10
3.00
2.90
2.80
2.70
2.60
3.50
2.50
1800
1600
1400
1200
1000
800
600
400
200
2000
0
Output Voltage V
OUT
(V)
Output Current I
OUT
(mA)
Time(sec)
-0.05
0.00
0.05
0.10
0.15
1800
1600
1400
1200
1000
800
600
400
200
2000
0
Output Current I
OUT
(mA)
3.45
3.40
3.35
3.30
3.25
3.20
3.15
3.10
3.05
3.50
3.00
Output Voltage V
OUT
(V)
R1225N
30
R1225N332A L=10uH V
IN
=7V
R1225N332A L=10uH V
IN
=7V
-0.0002 -0.0001 0.0000 0.0001 0.0002 0.0003 0.0004
3.40
3.30
3.20
3.10
3.00
2.90
2.80
2.70
2.60
3.50
2.50
1800
1600
1400
1200
1000
800
600
400
200
2000
0
Output Voltage V
OUT
(V)
Output Current I
OUT
(mA)
Time(sec)
Time(sec)
-0.05
0.00
0.05
0.10
0.15
1800
1600
1400
1200
1000
800
600
400
200
2000
0
Output Current I
OUT
(mA)
3.45
3.40
3.35
3.30
3.25
3.20
3.15
3.10
3.05
3.50
3.00
Output Voltage V
OUT
(V)
R1225N332B L=10uH V
IN
=4.8V
R1225N332B L=10uH V
IN
=4.8V
-0.0002 -0.0001 0.0000 0.0001 0.0002 0.0003 0.0004
3.40
3.30
3.20
3.10
3.00
2.90
2.80
2.70
2.60
3.50
2.50
1800
1600
1400
1200
1000
800
600
400
200
2000
0
Output Voltage V
OUT
(V)
Output Current I
OUT
(mA)
Time(sec)
Time(sec)
-0.04 -0.02
0
0.02
0.04
0.06
0.08
3.45
3.40
3.35
3.30
3.25
3.20
3.15
3.10
3.05
3.50
3.00
1800
1600
1400
1200
1000
800
600
400
200
2000
0
Output Voltage V
OUT
(V)
Output Current I
OUT
(mA)
R1225N332B L=10uH V
IN
=7V
R1225N332B L=10uH V
IN
=7V
-0.0002 -0.0001 0.0000 0.0001 0.0002 0.0003 0.0004
3.40
3.30
3.20
3.10
3.00
2.90
2.80
2.70
2.60
3.50
2.50
1800
1600
1400
1200
1000
800
600
400
200
2000
0
Output Voltage V
OUT
(V)
Output Current I
OUT
(mA)
Time(sec)
Time(sec)
-0.04 -0.02
0
0.02
0.04
0.06
0.08
3.45
3.40
3.35
3.30
3.25
3.20
3.15
3.10
3.05
3.50
3.00
1800
1600
1400
1200
1000
800
600
400
200
2000
0
Output Voltage V
OUT
(V)
Output Current I
OUT
(mA)
R1225N
31
R1225N332J L=27uH V
IN
=4.8V
R1225N332J L=27uH V
IN
=4.8V
-0.0002 -0.0001 0.0000 0.0001 0.0002 0.0003 0.0004
3.40
3.30
3.20
3.10
3.00
2.90
2.80
2.70
2.60
3.50
2.50
1800
1600
1400
1200
1000
800
600
400
200
2000
0
Output Voltage V
OUT
(V)
Output Current I
OUT
(mA)
Time(sec)
Time(sec)
-0.04 -0.02
0
0.02
0.04
0.06
0.08
3.45
3.40
3.35
3.30
3.25
3.20
3.15
3.10
3.05
3.50
3.00
1800
1600
1400
1200
1000
800
600
400
200
2000
0
Output Voltage V
OUT
(V)
Output Current I
OUT
(mA)
R1225N332J L=10uH V
IN
=7V
R1225N332J L=27uH V
IN
=7V
-0.0002 -0.0001 0.0000 0.0001 0.0002 0.0003 0.0004
3.40
3.30
3.20
3.10
3.00
2.90
2.80
2.70
2.60
3.50
2.50
1800
1600
1400
1200
1000
800
600
400
200
2000
0
Output Voltage V
OUT
(V)
Output Current I
OUT
(mA)
Time(sec)
Time(sec)
-0.04 -0.02
0
0.02
0.04
0.06
0.08
3.45
3.40
3.35
3.30
3.25
3.20
3.15
3.10
3.05
3.50
3.00
1800
1600
1400
1200
1000
800
600
400
200
2000
0
Output Voltage V
OUT
(V)
Output Current I
OUT
(mA)
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