LG KT520 Service Manual page 54

3.2.7 LCD Backlight Illumination
There are 5 white LEDs in LCD Backlight circuit which is driven by Charge Pump(MAX8631).
APP_GP10_BL_CTRL is used for Backlight brightness control.
APP_GP10_BL_CTRL
APP_GP15_CAM_LDO_CTRL
ESD9X5.0ST5G
INSTPAR
ZD101
Copyright © 2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
VBAT
C101
10u
C103
0.01u
BACKLIGHT CHARGE PUMP
Figure 3-2-10. Charge Pump Circuit LCD Backlight
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3. TECHNICAL BRIEF
U100 MAX8631XETI
1 23
PIN C1P
2
IN C100
1u
22
C1N
3 26
GND C2P
24
C102
PGND
29
1u
BGND
27
C2N
25
OUT
20
ENM1
19
ENM2
21 16
ENF M1
18 15
ENLDO M2
28 14
P1 M3
17 13
P2 M4
12
F1
11
F2
8 10
SETM F3
9
F4
7
SETF
4
LDO1
6 5
REFBP LDO2
C104 C105
1u 1u
VDD_BACKLIGHT
LCD_BL1
LCD_BL3
LCD_BL5
LCD_BL2
LCD_BL4
VDD_CAM_2V8
VDD_CAM_1V8
C106
10u
LGE Internal Use Only