High Efficiency 1X/1.5X/2X Charge
Pump for White LED Applications
Typical Characteristics
C
IN
= C
OUT
= C
1
= C
2
= 1.0µF; T
A
= 25°C, V
IN
= 3.6V, unless otherwise noted.
Efficiency vs. Supply Voltage
100
90
80
AAT3167
Turn-On to 1X Mode
(V
IN
= 4.2V; 18mA Load)
5.1mA
V
F
= 3.0V
18mA
V
F
= 3.4V
Efficiency (%)
70
60
50
40
30
20
10
0
2.5
2.8
3.0
3.3
3.5
3.8
4.0
4.3
4.5
4.8
5.0
5.3
5.5
EN
(2V/div)
OUT
(2V/div)
V
SINK
(500mV/div)
I
IN
(200mA/div)
350μA
V
F
= 2.7V
Supply Voltage (V)
Time (100µs/div)
Turn-On to 1.5X Mode
(V
IN
= 3.5V; 18mA Load)
Turn-On to 2X Mode
(V
IN
= 2.8V; 18mA Load)
EN
(2V/div)
OUT
(2V/div)
V
SINK
(500mV/div)
I
IN
(200mA/div)
EN
(2V/div)
OUT
(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; 18mA Load)
19.0
Current Matching vs. Temperature
EN
(2V/div)
18.8
18.6
Channel 2
Channel 3
Current (mA)
18.4
18.2
18.0
17.8
17.6
17.4
17.2
17.0
-40
-20
0
20
40
60
80
V
F
(1V/div)
Channel 1
Channel 4
Channel 5
I
IN
(100mA/div)
Time (100µs/div)
Temperature (°C)
°
3167.2007.03.1.4
5