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.
RM-180
System Module
Nokia Customer Care
Issue 1
COMPANY CONFIDENTIAL
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