AAT3151
High Efficiency 1X/1.5X/2X Charge Pump
For White LED Applications
Typical Characteristics
Efficiency vs. Supply Voltage
100
90
80
4.1mA
V
F
= 2.9V
Turn-On to 1X Mode
(V
IN
= 4.2V; 20mA Load)
Efficiency (%)
70
60
50
40
30
20
10
0
2.6
2.8
2.9
3.1
3.2
3.4
3.6
3.7
3.9
4.0
4.2
1mA
V
F
= 2.7V
10.2mA
V
F
= 3.1V
20mA
V
F
= 3.4V
EN
(2V/div)
CP
(2V/div)
V
SINK
(500mV/div)
I
IN
(200mA/div)
Time (100µs/div)
Supply Voltage (V)
Turn-On to 1.5X Mode
(V
IN
= 3.5V; 20mA Load)
Turn-On to 2X Mode
(V
IN
= 2.8V; 20mA Load)
EN
(2V/div)
CP
(2V/div)
V
SINK
(500mV/div)
I
IN
(200mA/div)
EN
(2V/div)
CP
(2V/div)
V
SINK
(500mV/div)
I
IN
(200mA/div)
Time (100µs/div)
Time (100µs/div)
Turn-Off from 1.5X Mode
(V
IN
= 3.5V; 20mA Load)
20.4
Current Matching vs. Temperature
EN
(2V/div)
Current (mA)
V
F
(1V/div)
20.2
20.0
19.8
19.6
19.4
19.2
19.0
-40
Channel 2
Channel 4
Channel 3
Channel 1
I
IN
(100mA/div)
-20
0
20
40
60
80
Time (500µs/div)
Temperature (°C)
°
3151.2005.12.1.7
5
ANALOGICTECH [ ADVANCED ANALOGIC TECHNOLOGIES ]
