Headset Interface - LG C3400 Service Manual

3.13 Headset Interface

This phone chooses a 6 pin type headset which has 6 electrodes such as GND, AUXIP,
AUXIN (this pin is floating), EAR_SPK_R, EAR_SPK_L, JACK_DETECT, HOOK_DETECT.
This type supports stereo sound
Switching from Receiver to Headset Jack
If jack is inserted, JACK_DETECT goes from low to high.
Audio path is switched from receiver to earphone by JACK_DETECT interrupt.
Switching from Headset Jack to Receiver
If jack is removed, JACK_DETECT goes from high to low.
Audio path is switched from earphone to receiver by JACK_DETECT interrupt.
Hook detection
If hook-button is pressed, HOOK_DETECT is changed from high to low.
This is detected by AUXADC2.
And then hook is detected.
C200
39p
JACK_DETECT
U200
JACK_DETECT
L REMOVE
H INSERT
C289 R203
0.1u
20K
AUXIN
R206
C204
20K
NA
2V8_VEXT 2V8_VEXT
R201
1M
EAR_SPK_L
AUXIP
5
4 VIN-
1 VCC
OUT 3 VIN+
GND
EAR_SPK_R
2
R230
330K
Figure 3-29. HEADSET JACK INTERFACE
2V5_JACK
R202
1K
R204 R211
1.5K 12K
C205 C206 C277
NA 22u 0.1u
C209 33u R210
R214 100 R213
C217 33u R228
R216
C212
39p
1M
- 41 -
3. TECHNICAL BRIEF
HOOK_DETECT
CLOSE TO EARJACK
0
4.7
0
J200
6
4
3
2
1
5