AAT3131_08 ANALOGICTECH [Advanced Analogic Technologies], AAT3131_08 Datasheet - Page 13

• Manufacturer Part Number: AAT3131_08
• Description: High Efficiency 1X/1.5X Fractional Charge Pump for White LED Applications
• Manufacturer: ANALOGICTECH [Advanced Analogic Technologies]

3131.2005.12.1.2
V
BATTERY
*In some applications, white LED forward voltages (V
for balancing the forward voltage differences. The ballast resistor value may be approximated by the following equation:
Figure 2: AAT3131 Driving Two Groups of Paralleled White LEDs
C
1µF
IN
EN/SET
(e.g., main LCD and sub-LCD backlights).
C
1µF
OUT
F
) can vary significantly. Ballast resistors between the LED cathodes and ground are recommended
VIN
VOUT
EN/SET
AAT3131
Charge Pump for White LED Applications
GND
C1-
C2-
D2
D3
C1+
C2+
D1
D4
R
B
=
V
SOURCE
High Efficiency 1X/1.5X Fractional
I
F
- V
F
C1
1µF
C2
1µF
R
D1
B
*
R
R
D2
D5
B
*
B
*
R
D6
D3
R
B
*
B
*
AAT3131
R
D4
B
*
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