LG VX5400, Руководство по обслуживанию

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of terminals. On the SDRAM data generated during the terminal operation are stored temporarily.
2.3.5 Power Supply Part
When the battery voltage (+4.0V) is fed and the PWR key of keypad is pressed, the power-up circuitry in PM
(power management) IC (U500) is activated by the PWR_ON_SW signal, and then the LDO regulators
embedded in PMIC for MSM) are operated and +1.867V_MSMC, +2.85V_MSMP and +2.6V_MSMA are
generated.
The Rx part regulator (+2.85V_RX) is operated by the control signal of SLEEP/ from MSM6100.
The Tx part regulator (+3.0V_TX) is operated by the I
2
C control signal from MSM6100.
2.3.6 Logic Part
The logic part consists of internal CPU of MSM, RAM, MCP. The MSM6100 receives TCXO (=19.2MHz)
from X100 and controls the phone in both CDMA and FM modes. The major components are as follows:
z
CPU
The ARM9TDMI microprocessor includes a 3 stage pipelined RISC architecture, both 32-bit ARM and 16-bit
THUMB instruction sets, a 32-bit address bus, and a 32-bit internal data bus. It has a high performance and
low power consumption.
z
MCP
Flash ROM is used to store the terminal’s program. Using the down-loading program, the program can be
changed even after the terminal is fully assembled.
SDRAM is used to store the internal flag information, call processing data, and timer data.
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KEYPAD
For key recognition, key matrix is setup using KYPD[1][3][5][7][9][11][13][15][17][19] signal from MSM.
20 LEDs and backlight circuitry are included in the keypad for easy operation in the dark.
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LCD MODULE
LCD module contains a controller which will display the information onto the LCD by 16-bit data from the
MSM6100. It is also supplied stable 2.85V_MSMP by regulator in U402 for fine view angle and LCD reflects
to improve the display efficiency. 4 LEDs are used to display LCD backlight.
Copyright@2007 LG Electronics. Inc. All right reserved. LGE Internal Use Only
Only for training and serving purposes
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