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LGE Internal Use Only
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Only for training and service purposes
3. TECHNICAL BRIEF
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LGE Property
3.10 LCD back-light illumination
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Figure 12 LCD Back light unit and Flash LED charge pump IC
The RT9393 is a write-only single wire interface. It provides access to up to 32 registers that control device
functionality. In this system, two sets of pulse trains are transmitted via the SPIF pin. The first pulse set is used to
set the desired address. After the bus is held high for the address hold period, the next pulse set is used to write
the data value. After the data pulses are transmitted the bus is held high again for the data hold period to signify
the data write is complete. At this point the slave device latches the data into the address that was selected by
the first set of pulses. The protocol for using this interface is described in the following subsection.
Figure 13 I2C Serial data port control method
02
4
R
0
U400
14
13
12
11
10
9
8
7
6
5
4
3
2
1
GND
C2N
C1N
C1P
C2P
VIN
EN
LED6
LED5
LED4
LED3
LED2
LED1
VOUT
MLED
VBAT
C409
1uF
C411
1uF
s
mh
o
K0
01
21
4
R
1uF
C412
C415
1uF
LCD_BACKLIGHT_EN
MLED5
MLED4
MLED3
MLED2
MLED1
LCD Backlight