Total Power Solution for Portable Applications
Typical Characteristics—Step-Down Converter
P-Channel R
DS(ON)
vs. Input Voltage
750
700
650
750
700
AAT2550
N-Channel R
DS(ON)
vs. Input Voltage
R
DS(ON)H
(mΩ)
Ω
R
DS(ON)L
(mΩ)
Ω
120°C
100°C
650
600
550
500
450
400
350
300
25°C
120°C
100°C
600
550
500
450
400
350
300
2.5
3.0
3.5
4.0
4.5
5.0
5.5
6.0
25°C
85°C
85°C
2.5
3.0
3.5
4.0
4.5
5.0
5.5
6.0
Input Voltage (V)
Input Voltage (V)
Load Transient Response
(1mA to 300mA; V
IN
= 3.6V; V
OUT
= 1.8V;
C
1
= 10μF; C
FF
= 100pF)
μ
2.0
1.9
1.90
1.85
Load Transient Response
(300mA to 400mA; V
IN
= 3.6V;
V
OUT
= 1.8V; C
1
= 4.7μF)
μ
Load and Inductor Current
(200mA/div) (bottom)
Load and Inductor Current
(200mA/div) (bottom)
V
O
I
O
I
L
V
O
I
O
Output Voltage
(top) (V)
1.7
300mA
1mA
Output Voltage
(top) (V)
1.8
1.80
1.75
400mA
300mA
0.4
0
I
L
Time (50μs/div)
0.3
0.2
0.1
Time (50μs/div)
Load Transient Response
(300mA to 400mA; V
IN
= 3.6V;
V
OUT
= 1.8V; C
1
= 10μF)
μ
1.90
1.85
Load Transient Response
(300mA to 400mA; V
IN
= 3.6V; V
OUT
= 1.8V;
C
1
= 10μF; C
4
= 100pF)
μ
1.850
1.825
Load and Inductor Current
(200mA/div) (bottom)
Load and Inductor Current
(200mA/div) (bottom)
V
O
I
O
V
O
I
O
400mA
300mA
0.4
Output Voltage
(top) (V)
1.75
Output Voltage
(top) (V)
1.80
1.800
1.775
400mA
300mA
0.4
I
L
0.3
0.2
0.1
I
L
0.3
0.2
0.1
Time (50μs/div)
Time (50μs/div)
8
2550.2006.07.1.0
ANALOGICTECH [ ADVANCED ANALOGIC TECHNOLOGIES ]
