Internal Speakers; External Earpiece - Nokia MOBILE TERMINAL Service Manual

RM-356
System Module and User Interface
Figure 76 Internal earpiece circuitry

Internal speakers

Internal speakers is used for Internal HandsFree (IHF) call mode, video call, ringing tones, FM radio and music
listening.
The two speakers are connected to Avilma ASIC's outputs XearR/XearL via the stereo D-class IHF amplifier
TPA2012D2. The amplifier has 24 dB fixed gain and it is put to shutdown mode when not in use.
Figure 77 Internal speakers' circuitry

External earpiece

Galvanic accessories are connected to the AV connector.
Accessory audio mode is automatically enabled/disabled during connection/disconnection of dedicated
phone accessories.
The Avilma ASIC provides two output channels in either single-ended or differential format. The Avilma ASIC
outputs XearL and XearLC form the left channel audio output, and XearR and XearRC from the right channel
audio output. XearLC and XearRC are the ground pins if the output works in a single-ended operation.
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