LG KD3500 Service Manual page 22

LG-KD3500
2.3.2.1 Audio Processing Part
MIC signals are inputted into the audio codec, and amplified with programmable gain, and converted
into digital signals(PCM). Then, they are inputted into QSC6010.
In addition, digital audio signals(PCM) outputted from QSC6010 are converted into analog signals
after going through the audio codec. These signals are amplified with programmable gain on codec's
internal AMP and external MIDI Synthesizer, transferred to the ear-piece.
2.3.3 Memory Part
The memory part consists of a 64Mbits Flash Memory and a 32Mbits SRAM. On the Flash Memory,
there are programs used for the operation of a mobile station and the non-volatile data of the mobile
station such as a ESN(Electronic Serial Number) are stored. The programs can be changed through
down loading after the assembling of mobile stations. On the SRAM, data generated during the
operation of a mobile station are stored temporarily.
2.3.4 Power Supply Part
When the battery voltage (+4.2V) is fed and the PWR key of keypad is pressed, the power-up circuitry
in QSC6010(U201) is activated by the PWR_ON_SW/ signal, and then the LDO regulators embedded
in QSC6010 are operated and +2.80V_MSMC, +2.85V_MSMP and +2.6V_MSMA are generated.
LGE
LG Electronics Inc.
20/21