Earphone Trouble - LG L1100 Service Manual

4.14 Earphone Trouble

Block Diagram
Earphone Detecting Operation
• The DBB read JACK_DETECT port periodically and if the voltage of "JACK_DETECT" goes to 0V, it
detects ear-jack inserted.
•The ABB operates A/D conversion continuously and if the voltage of "HOOK_DETECT" node goes to
about 40mV, it detects hook switch is pushed in call state.
Earphone Sending Path
• HSMICP is the audio signal from the microphone of the earphone.
•R215, R216 and C219 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).
• R232,C223,R298 and R299 make the path of the audio signal from ABB to earphone.
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EAR_JACK SPEC
Receiver GND
MIC