External Microphone - Nokia MOBILE TERMINAL Service Manual

RM-356
System Module and User Interface

External microphone

Galvanic accessories are connected to the AV connector.
Accessory audio mode is automatically enabled/disabled during connection/disconnection of dedicated
phone accessories.
External microphone circuitry is biased by Avilma ASIC MicB2 bias voltage output. The circuitry provides an
asymmetrical connection for the microphone from the AV connector, XMICP to Avilma ASIC input, mic2p and
XMICN, to GND.
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