LG 501C Service Manual page 40

LG501C
[Figure 2-2] Block Diagram of Digital/Voice Processing Part
2.3.4 Memory Part
MCP contents 2Gbits NAND flash memory and 1Gbits DDR SDRAM. In the Flash Memory part of MCP
are programs used for terminal operation. The programs can be changed through down loading after the
assembling 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) circuit(in QSC6055) is activated by the PWR_ON_SW/ signal, and then the
LDO regulators embedded in PM circuit are operated and +1.3V_MSMC, +2.6V_MSMP, +1.8V_MSME1
and +2.1V_MSMA are generated.
The Rx part (+2.1V_RFRX) and Tx part voltage (+2.1V_RFTX) are regulated by QSC6055
2.3.6 Logic Part
The logic part consists of internal CPU of QSC, RAM, MCP. The QSC6055 receives 19.2MHz clock from
X2201 and controls the phone in both CDMA and GPS modes. The major components are as follows:
CPU
The ARM926 EJS 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.
LG Electronics Inc.
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