AAT2806
Dual High Efficiency Charge Pump
for White LED and Flash Applications
Typical Characteristics– White LED Backlight Driver Section
Turn-On to 1X Mode
(V
IN
= 4.2V; 20mA Load)
Turn-On to 1.5X Mode
(V
IN
= 3.5V; 20mA Load)
EN
(2V/div)
CP
(2V/div)
V
SINK
(500mV/div)
I
IN
(200mA/div)
Time (100µs/div)
EN
(2V/div)
CP
(2V/div)
V
SINK
(500mV/div)
I
IN
(200mA/div)
Time (100µs/div)
Turn-On to 2X Mode
(V
IN
= 2.8V; 20mA Load)
EN
(2V/div)
V
F
(1V/div)
Turn-Off from 1.5X Mode
(V
IN
= 3.5V; 20mA Load)
EN
(2V/div)
CP
(2V/div)
V
SINK
(500mV/div)
I
IN
(200mA/div)
I
IN
(100mA/div)
Time (100µs/div)
Time (500µs/div)
Efficiency vs. Supply Voltage
100
10mA
V
F
= 3.1V
90
20mA
V
F
= 3.4V
20.4
20.2
Current Matching vs. Temperature
Channel 2
Channel 4
Channel 3
Channel 1
Efficiency (%)
Current (mA)
20.0
19.8
19.6
19.4
19.2
19.0
80
70
60
50
2.8
3.0
3.2
3.4
3.6
3.8
4.0
4.2
-40
-20
0
20
40
60
80
Supply Voltage (V)
Temperature (°C)
°
2806.2007.09.1.9
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