Multi-Mode Charge Pump for
White LED Backlight and Flash Applications
Typical Characteristics–White LED Backlight Driver Section
V
IN
= 3.5V, C
IN
= 2.2µF, C
CP
= C1 = C2 = 1.0µF; T
A
= 25°C, unless otherwise noted.
AAT2801
Charge Pump to Load Switch
(1.5X Mode; 4x19mA Load)
V
IN
(500mV/div)
V
CP
(1V/div)
V
DIODE
(500mV/div)
I
IN
(50mA/div)
Charge Pump to Load Switch
(1.5X Mode; 4x30mA Load)
V
IN
(500mV/div)
V
CP
(1V/div)
V
DIODE
(500mV/div)
I
IN
(50mA/div)
Time (5ms/div)
Time (5ms/div)
Charge Pump to Load Switch
(2X Mode; 4x19mA Load)
Charge Pump to Load Switch
(2X Mode; 4x30mA Load)
V
IN
(500mV/div)
V
CP
(1V/div)
V
DIODE
(500mV/div)
I
IN
(50mA/div)
V
IN
(500mV/div)
V
CP
(1V/div)
V
DIODE
(500mV/div)
I
IN
(50mA/div)
Time (5ms/div)
Time (5ms/div)
Load Switch to Charge Pump
(1.5X Mode; 4x19mA Load)
V
IN
(1V/div)
V
CP
(4V/div)
V
DIODE
(500mV/div)
I
IN
(50mA/div)
V
IN
(1V/div)
V
CP
(4V/div)
V
DIODE
(500mV/div)
I
IN
(50mA/div)
Load Switch to Charge Pump
(1.5X Mode; 4x30mA Load)
Time (2ms/div)
Time (2ms/div)
2801.2006.04.1.3
7
ANALOGICTECH [ ADVANCED ANALOGIC TECHNOLOGIES ]
