LG C1100, Service Manual, Page: 21 / 127

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3. TECHNICAL BRIEF
3.5.1 Interconnection with external devices
A. RTC Block Interface
Countered by external X-TAL
The X-TAL oscillates 32.768KHz
B. LCD module interface
The LCD module is controlled by DBB chipset, AD6525.
When LCD operate, the AD6525 controls the LCD module through LCD_CS, LCD_RESET,
ADD01, WR, DATA[00-15]. LCD_ID, LCD_RESET
Table 3-3. LCD module interface
C. RF Interface
The AD6525 control RF parts through PA_BAND, ANT_SW1, ANT_SW2, CLKON , PA_EN,
S_EN, S_DATA, S_CLK, RF_PWR_DWN
Table 3-4. RF CONTROL SIGNALS DISCRIPTION
Signals Description
LCD_CS MAIN LCD driver chip enable. MAIN LCD driver IC has own CS pin
LCD_RESET This pin resets LCD module.
This pin determines whether the data to LCD module are display data
ADD1(RS) or control data. ADD1 can select 16 bit parallel bus. ADD1 is also
used to address flash memory.
WR Write control. The phone do not read data from LCD chip.
DATA
Parallel data lines. Color LCD driver chip uses the 16-bit data
interface.
2V8_VMEM 3V voltage is supplied to white colored LED driver for backlighting.
LCD_BACKLIGHT Control signal of white LED driver IC.
DATA[00-15] Parallel data lines, Sub LCD driver chip uses the 8-bit data in reface.
GPO Signal Name Description
17 PA_BAND PAM Band Select
9 ANT_SW1 Antenna Switch Band Select
11 ANT_SW2 Antenna Switch Band Select
- CLKON RF LDO Enable/Disable
16 PA_EN PAM Enable/Disable
19 S_EN PLL Enable/Disable
20 S_DATA Serial Data to PLL
21 S_CLK Clock to PLL
4 RF_PWER_DWN Powerdown Input