Digital/Voice Processing Part - LG ID2750 Service Manual

LG-ID2750

2. Digital/Voice Processing Part

2.1 Overview
The digital/voice processing part processes the user's commands and processes all the digital and
voice signal processing in oIDer to operate in the phone. The digital/voice processing part is made up
of a keypad/LCD, receptacle part, voice processing part, mobile station modem part, memory part,
and power supply part.
2.2 Configuration
2.2.1 Keypad/LCD and Receptacle Part
This is used to transmit keypad signals to MSM6000. It is made up of a keypad backlight part that
illuminates the keypad, LCD part that displays the operation status on to the screen, and a receptacle
that receives and sends out voice and data with external sources.
2.2.2 Voice Processing Part
The voice processing part is made up of an audio codec in MSM6000 used to convert MIC signals into
digital voice signals and other external MIDI Synthesizer used to convert digital voice signals into
analog voice signals, amplifying parts for amplifying the voice signals and MIC signals are on external
MIDI Synthesizer and Codec in MSM6000.
2.2.3 MSM6000 (Mobile Station Modem) Part
MSM6000 is the core elements of a CDMA mobile station and carries out the functions of CPU,
encoder, interleaver, deinterleaver, Viterbi decoder, Mod/Demod, codec, and vocoder.
2.2.4 Memory Part
The memory part is made up of a flash memory, SRAM for storing data.
2.2.5 Power Supply Part (U400, PM6610-2)
The power supply part (PM6610) is made up of devices for generating various types of power, used
for the digital/voice processing part and one DC/DC converter directly connetted to Batterry for LCD
display.
LGE
LG Electronics Inc.
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