Service Manual

3.2 Configuration
3.2.2 Voice Processing Part
The voice processing part is made up of an audio codec into digital voice signals and digital voice signals into
analog voice signals, amplifying part for amplifying the voice signals and sending them to the ear piece, amplifying
part that amplifies ringer signals coming out from MSM3000, and amplifying part that amplifies signals coming out
from MIC and transferring them to the audio processor.
3.2.3 MSM (Mobile Station Modem) Part
MSM is the core elements of CDMA terminal and carries out the functions of CPU, encoder, interleaver,
deinterleaver, Viterbi decoder, Mod/Demod, and vocoder.
3.2.4 Memory Part
The memory part is made up of a flash memory, SRAM for storing data, and EEPROM.
3.2.5 Power Supply Part
The power supply part is made up of circuits for generating various types of power, used for the digital/voice
processing part.
+4.2V from external DC (+6V) is fed into five regulators(U605,U603,U602,U604,U606).
The five regulators produces +3.0V for the IFR3000(U204) and for Tx Parts.
3.3 Circuit Description