V1.20 Page 46 of 48 ICM MP CCQ GRM
A55/C55_Hitachi Company Confidential © Copyright Siemens AG 04/03
8.2 Earpiece/Loudspeaker
8.2.1 Mechanical
The speakermodule is designed to provide optimal performance for mobile handsfree
and sound ringer. Plus independent from mobile leakage sound performance.
Therefore speakermodule is a system that has a closed front volume with sound-
outlets towards the ear of the user. Backvolume of Speakermodule is using the
unused air between the antenna and the PCB. Backvolume is just used for resonance,
there is no sound output from backvolume. The speakermodule is glued to the
lightguide and contacted via two bending springs to the PCB. The lightguide itself is
screwed with six screws via the PCB to the mounting frame lower part. Two of the six
screws are located besides of the connection of speakermodule and lightguide.
Therefore a good and reliable connection between speakermodule and PCB should
be provided.
8.2.2 Electrical
The internal and external Loudspeaker (Earpiece) is connected to the voiceband part
of the EGOLD+ (
Analog Interface B1, C1) via audio amplifier inside the ASIC (D361). Input
EPN1_FIL - EPP1_FIL. Output for external loudspeaker AUDIO_L - AUDIO_R, for
internal Loudspeaker EPP! – EPN1. The ringing tones are generated with the
loudspeaker too. To activate the ringer, the signal RINGIN from the EGOLD+
(
Miscellaneous,D16) is used
EGOLD+
from Bright
IC
to ASIC