LG KF750 Service Manual page 60

B. Voice Call Uplink Mode (Receiver,Speaker,Headset)
This section provides a detailed description of the Voice Call TX functions.
From the audio path view point, voice call has the same structure as video telephony. The TXMIX
connection enables insertion of audio into the uplink audio path. This can, for example, be used to play
dictation recordings for the listener at the other party, in a voice call or video telephony call. The
connection to TXMIX from the Audio Mixer must be performed in 8 kHz mono, since this is supported
by the Voice mode. Due to performance reasons it may not be possible to decode every audio format
during video telephony.
Each Voice Uplink Mode paths shown below.
• Receiver Mode : C-MIC(SP0102BE3) → Veronica Input(MIC1N/1P)
• Loud Speaker Mode : C-MIC(SP0102BE3) → Veronica Input(MIC1N/1P)
• Video Telephony Mode : C-MIC(SP0102BE3) → Veronica Input(MIC1N/1P)
• Headset Mode : Headset MIC → Veronica Input(AUXI1N/1P)
When the headset is inserted, EAR_DETECT_n(Circuit Diagram net Name) converted into low state
So, the headset icon is displayed on Main LCD.
Copyright © 2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
Figure 3-3-5. Voice call Uplink Scheme
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3. TECHNICAL BRIEF
LGE Internal Use Only