PRODUCT DATASHEET
AAT2550178
SystemPower
TM
Total Power Solution for Portable Applications
Typical Characteristics — Step-Down Converter (continued)
Soft Start
(V
IN
= 3.6V; V
OUT
= 1.8V; I
OUT
= 400mA)
Enable and Output Voltage
(top) (V)
5.0
4.0
3.0
2.0
1.0
0.0
0.6
0.4
0.2
0.40
0.30
Line Regulation
(V
OUT
= 1.8V)
V
EN
V
O
Inductor Current
(bottom) (A)
Accuracy (%)
0.20
0.10
0.00
-0.10
-0.20
-0.30
-0.40
2.5
3.0
3.5
I
OUT
= 10mA
I
OUT
= 1mA
I
OUT
= 400mA
I
L
0.0
-0.2
-0.4
4.0
4.5
5.0
5.5
6.0
μ
Time (100μs/div)
Input Voltage (V)
Output Voltage Error vs. Temperature
(V
IN
= 3.6V; V
O
= 1.8V; I
OUT
= 400mA)
2.0
15.0
12.0
9.0
Switching Frequency vs. Temperature
(V
IN
= 3.6V; V
OUT
= 1.8V)
Output Error (%)
Variation (%)
1.0
6.0
3.0
0.0
-3.0
-6.0
-9.0
-12.0
-15.0
-40
0.0
-1.0
-2.0
-40
-20
0
20
40
60
80
100
-20
0
20
40
60
80
100
Temperature (°C)
°
Temperature (°C)
°
Frequency vs. Input Voltage
2.0
No Load Quiescent Current vs. Input Voltage
50
Frequency Variation (%)
1.0
0.0
-1.0
V
OUT
= 1.8V
Supply Current (μA)
μ
45
40
35
30
25
20
15
10
85°C
25°C
V
OUT
= 2.5V
-2.0
-3.0
-4.0
2.7
3.1
3.5
3.9
V
OUT
= 3.3V
-40°C
2.7
3.1
3.5
3.9
4.3
4.7
5.1
5.5
4.3
4.7
5.1
5.5
Input Voltage (V)
Input Voltage (V)
2550.2008.02.1.3
www.analogictech.com
7
ANALOGICTECH [ ADVANCED ANALOGIC TECHNOLOGIES ]
