Earphone Trouble - LG G5500 Manual

4.14 Earphone Trouble

Block Diagram
Earphone Detecting Operation
• The DBB read JACK_DETECT port periodically and if the voltage of Pin1 of U304 goes to High and
the voltage at "JACK_DETECT" 2.8V, it detects ear-jack inserted.
• The ABB operates A/D conversion continuously and if the voltage of "HOOK_DETECT" node goes
to 0V, it detects hook switch is pushed.
Earphone Sending Path
• HSMICP is the audio signal from the microphone of the earphone.
• L305, L303 and C318 make the path of the audio signal from the microphone of the earphone.
• This audio signal is delivered to ABB(IOTA).
Earphone Receiving Path
• HSO is the audio signal from ABB(IOTA).
U102(IOTA)
To U102(IOTA)
-76-
EAR_JACK SPEC
From
VCC
MIC
The direction of the audio
Signal from ear-mic
Vcc
CAM
EAR HSMICP
DP GND
GND
SOUND
GND
D+ D-
HSO
N,C
GND