LG C3400 Service Manual page 29

3. TECHNICAL BRIEF
3.6.4 Audio Section
1. Receive audio signal from microphone.C3400 uses differential configuration.
2. Send audio signal to speaker.C3400 uses differential configuration.
3. This section provides an audio codec with a digital-to-analog converter and an analog- to-
digital converter,a ring tone volume controller,a microphone interface,and multiple analog
input and output channels.
4. It interconnects with external devices like main microphone,main receiver,and headset.
The descriptions of audio port used in C3400 are given bellow in detail.
<Up Link>
-AIN1P,AIN1N :Main microphone positive/negative terminal
-AIN2P,AIN2N :Headset microphone positive/negative terminal
-AIN3L,AIN3R :External Analog Input terminal
<Down Link>
-AOUT1P,AOUT1N :Main Speaker positive/negative terminal
-AOUT3L,AOUT3R :Headset speaker Left /Right terminal
AD6535
GPI
CSFS
CSDI
CSDO
ASFS
ASDI
ASDO
Control
Ring Tone
Serial
Volume Controller
Port
Audio
Serial
Port
Filter /
SRC
Filter /
SRC
Filter /
ADC
SRC
Figure 3-15.AD6535 AUDIO SECTION
+
Analog PGA 3
Adder
Analog
Adder
PGA 1
DAC
+
1
PGA 2
DAC
+
2
Analog
Adder
Microphone Interface
PGA
Gain Pre-Amp
- 28 -
AIN3R
AIN3L
Analog
SPWR
Switch
AOUT2P
AOUT2N
SGND
Analog
Switch AOUT1P
AOUT1N
AOUT3L
AOUT3R
AIN1P
AIN1N
AIN2P
AIN2N
8 Ω
32 Ω
32 Ω
32 Ω