Internal Microphone; External Microphone - Nokia N72 Service Manual

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System Module Nokia Customer Care
Figure 101 Audio block diagram

Internal microphone

Internal microphone is used for HandPortable (HP) and Internal HandsFree (IHF) call modes.
An analogue electret microphone is connected to N2200 Mic1P and Mic1N inputs via asymmetric electrical
connection.
The microphone is biased by N2200 MicB1 bias voltage output.
Figure 102 Internal microphone circuitry

External microphone

Galvanic accessories are connected to the system connector.
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