LG L705ix Service Manual page 51

3. TECHNICAL BRIEF
3.11.6 Audio Interface
3.11.6.1 Audio Signal Processing & Interface
Audio signal processing is divided uplink path and downlink path.
The uplink path amplifies the audio signal from MIC and converts this analog signal to digital signal
and then transmits it to DBB Chip (MSM6280).
This transmitted signal is reformed to fit in WCDMA frame format and delivered to RF Chipset. The
downlink path amplifies the signal from DBB chip (MSM6280) and outputs it to receiver (or speaker).
The receive path can be directed to either one of two earphone amplifiers or the auxiliary output.
The outputs earphone1 (EAR1OP, EAR1ON) and auxiliary out (AUXOP, AUXON) are differential
outputs. Earphone2 (EAR2/EAR3) is a single-ended output stage designed to drive a headset
speaker. The microphone interface consists of two differential microphone inputs, one differential
auxiliarym input and a two-stage audio amplifier.
Figure.3.11.8 Audio Interface Detailed Diagram(MSM6280)
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