LG LG-YD636, Руководство по обслуживанию

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LDO(in PMIC) for +2.60V_TX part is enabled on traffic state, and gives the power TX part devices.
LDO(in PMIC) for +2.60V_RX part is enabled on idel state, and gives the power RX part devices.
Turn OFF
When the PWR key is pressed during a few seconds, PMIC is turned on by PWR_ON_SW/ and
then, 'Low' is outputted on PS_HOLD. MSM6025 receives this signal and then, recognizes that the
POWER key has been pressed. During this time, MSM6025 outputs PS_HOLD as low and turn off
all devices
2.3.7 Logic Part
The Logic part consists of internal CPU of MSM6025, MCP(SRAM& FLASH MEMORY) .
The MSM6025 receives TCXO (=19.2MHz) from U101 and controls the phone in both CDMA and FM
modes. The major components are as follows:
CPU : ARM7TDMI microprocessor core
MEMORY :
•
FLASH SRAM : 64M bits(Flash) + 32M bits(SRAM)
CPU
ARM7TDMI 32-bit microprocessor is used and CPU controls all the circuitry. Some of the features of
the ARM microprocessor include a 3 stage pipelined RISC architecture, both 32-bit ARM and 16bit
THUMB instruction setsm, a 32-bit address bus, and a 32-bit internal data bus.
FLASH Memory
Flash Memory is used to store the program of the mobile station. Using the down-loading program,
the program can be changed even after the mobile station is fully assembled.
SRAM
SRAM is used to store the internal flag information, call processing data, and timer data.
KEYPAD
For key recognition, key matrix is setup using KEY_SENSE0/-3/ signals and GPIO57-61, GPIO21 of
output ports of MSM. Backlight circuitry are included in the keypad for easy operation in the dark.
LCD MODULE
LCD module contains a controller which will display the information onto the LCD by 16-bit data from
the MSM6025. It is consist of one LCD with 128(W) X 128(H) dots 65,000 STN Color.
It is also supplied 2.85V_MSMP by PMIC for fine view angle and LCD reflects to improve
the display efficiency. White LEDs are used to display LCD backlight.