LG U310 Service Manual page 61

3. TECHNICAL BRIEF
3.10.11.2. 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 transmit it to DBB Chip (MSM6250A). This transmitted signal is reformed to fit in GSM &
WCDMA Frame format and delivered to RF Chip. The downlink path amplifies the signal from DBB
chip (MSM6250A) 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 (EAR2O) is a single-ended output stage designed to drive a headset speaker.
The microphone interface consists of two differential microphone inputs, one differential auxiliary input
and a two-stage audio amplifier.
Figure Audio Interface Detailed Diagram(MSM6250A)
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