MIC23250 Datasheet, PDF (4/15 Pages) Micrel Semiconductor – 4MHz Dual 400mA Synchronous Buck Regulator with HYPER LIGHT LOAD™

Micrel, Inc.
Typical Characteristics
Quiescent Current
vs. Input Voltage
50
45
40
35
30
25
20
15
10
L = 1µH
5
C_OUT = 4.7µF
0
2.7 3.2 3.7 4.2 4.7 5.2 5.7
INPUT VOLTAGE (V)
Frequency
vs. Temperature
5.0
4.5
4.0
3.5
L = 1µH
C_OUT = 4.7µF
Load = 120mA
3.0
20 40 60 80
TEMPERATURE (°C)
Output Voltage
vs. Temperature
1.9
VOUT2 = 1.8V
1.8
L = 1µH
1.7
C_OUT = 4.7µF
Load = 120mA
1.6
VOUT1 = 1.575V
1.5
20 40 60 80
TEMPERATURE (°C)
Current Limit
vs. Input Voltage
700
650
600
5520.7
L = 1µH
C_OUT = 4.7µF
3.2 3.7 4.2 4.7 5.2 5.7
INPUT VOLTAGE (V)
December 2007
Switching Frequency
vs. Output Current
10
4MHz
1
V_IN = 3.0V
0.1
0.01
1
V_IN = 4.2V
V_OUT = 1.8V
L = 1µH
V_IN = 3.6V
C_OUT = 4.7µF
10
100
1000
OUTPUT CURRENT (mA)
1.90
1.88
1.86
1.84
1.82
1.80
1.78
1.76
1.74
1.72
1.701
Output Voltage
vs. Output Current
VIN = 3.0V
VIN = 4.2V
VIN = 3.6V
10
100
1000
OUTPUT CURRENT (mA)
Enable Threshold
vs. Temperature
1.2
1.0 ^{VIN = 3.6V}
0.8 _{VIN = 2.7V}
VIN = 5.5V
0.6
0.4
0.2
L = 1µH
C_OUT = 4.7µF
0
20 40 60 80
TEMPERATURE (°C)
Efficiency V_OUT = 1.8V
100
90 ^{VIN = 2.7V VIN = 3.0V}
80
70 VIN = 4.2V
VIN = 3.6V
60
50
40
30
20
10
L = 1µH
C_OUT = 4.7µF
01
10
100
1000
LOAD (mA)
4
MIC23250
Switching Frequency
vs. Output Current
10
L = 4.7µH
4MHz
1
L = 1µH
0.1
0.011
L = 2.2µH
V_IN = 3.6V
V_OUT = 1.8V
C_OUT = 4.7µF
10
100
1000
OUTPUT CURRENT (mA)
Output Voltage
vs. Input Voltage
1.90
1.88
L = 1µH
C_OUT = 4.7µF
1.86
1.84
1.82
Load = 10mA
Load = 1mA
1.80
1.78
Load = 150mA
1.76 Load = 50mA
Load = 300mA
1.74
Load = 400mA
1.72
1.720.7 _{3.2 3.7 4.2 4.7 5.2 5.7}
INPUT VOLTAGE (V)
1.000
Enable Threshold
vs. Input Voltage
0.975
0.950
0.925
0.900
Enable ON
Enable OFF
0.875
0.850
0.825
0.800
2.7
V_IN = 3.6V
V_OUT = 1.8V
Load = 150mA
3.2 3.7 4.2 4.7 5.2 5.7
INPUT VOLTAGE (V)
Efficiency V_OUT = 1.8V
100
90
80
70
60
50
40
30
20
10
01
L = 1.5µH
L = 1.0µH
L = 0.47µH
V_IN = 3.6V
C_OUT = 4.7µF
10
100
LOAD (mA)
1000
M9999-121707-A