Microphone - LG C1150 Service Manual

3.10 Microphone

The microphone is placed to the front cover and contacted to main PCB. The audio signal is
passed to AIN1P and AIN1N pins of AD6537B. The voltage supply VMIC is output from
AD6537B, and is a bias voltage for the AIN1P. The AIN1P and AIN1N signals are then A/D
converted by the Voiceband ADC part of AD6537B. The digitized speech is then passed to
the DSP section of AD6525 for processing (coding, interleaving etc.).
AD6537B
AIN1P
AIN1N
1k
2.2k
100
39p
39p
100
0.1u
39p
Figure 3-24. MICROPHONE
- 43 -
3. TECHNICAL BRIEF
VMIC
39p
10u
39p
39p 39p
2.2k
Main Mic