AAT2556
Battery Charger and Step-Down
Converter for Portable Applications
Typical Characteristics – Step-Down Converter
Load Transient Response
(10mA to 250mA; VIN = 3.6V; VOUT = 1.8V;
Load Transient Response
(10mA to 250mA; VIN = 3.6V; VOUT = 1.8V; COUT = 4.7µF)
C
OUT = 4.7µF; CFF = 100pF)
2.0
1.9
1.8
1.7
1.6
1.5
1.4
1.3
1.2
2.0
1.9
1.8
1.7
1.6
1.5
1.4
1.3
1.2
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0.0
-0.2
VO
VO
IO
IO
ILX
ILX
Time (25µs/div)
Time (25µs/div)
Line Response
(VOUT = 1.8V @ 250mA; CFF = 100pF)
Output Ripple
(VIN = 3.6V; VOUT = 1.8V; IOUT = 1mA)
40
20
0.07
0.06
0.05
0.04
0.03
0.02
0.01
0.00
-0.01
1.90
1.85
1.80
1.75
1.70
1.65
1.60
1.55
1.50
7.0
6.5
6.0
5.5
5.0
4.5
4.0
3.5
3.0
VO
VO
0
-20
-40
-60
-80
-100
-120
VIN
IL
Time (25µs/div)
Time (2µs/div)
Output Ripple
(VIN = 3.6V; VOUT = 1.8V; IOUT = 250mA)
40
20
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0.0
VO
0
-20
-40
-60
-80
-100
-120
IL
Time (200ns/div)
8
2556.2006.09.1.2
AAT [ ADVANCED ANALOG TECHNOLOGY, INC. ]
