Figure 60 Audio block diagram
The internal microphone is used for HandPortable (HP) and Internal HandsFree (IHF) call modes. Also if the
accessory headset does not have microphone, the phone uses the internal microphone. An analogue electret
microphone is connected to the EM ASIC N2200 Mic1P input via asymmetric electrical connection. The
microphone is biased by the EM ASIC MicB1 bias voltage output.
Figure 61 Internal microphone
Galvanic accessories are connected to the 3.5mm AV-connector. Accessory audio mode is automatically
enabled/disabled during connection/disconnection of dedicated phone accessories. External microphone is
connected to EM ASIC N2200 input Mic2P and Mic2N. Mic2P, Head_Det line of EM ASIC N2200 and Composite
Video input from application ASIC are multiplexed to the same AV-connector line.
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