TDA7416_11 Datasheet, PDF (22/37 Pages) STMicroelectronics – Car radio signal processor

Description of the audio processor part
TDA7416
4.10
AC coupling
In some applications additional signal manipulations are desired. For this purpose an AC-
coupling is placed before the speaker (fader)-attenuators, which can be activated or
internally shorted by I²C bus. In short condition the input-signal of the speaker-attenuator is
available at the AC-outputs. The input-impedance of this AC-inputs is 50k. In addition there
are Mix inputs available. With this inputs it is possible to mix an external signal to every
speaker with a mixing ratio of 50% (seeFigure 16).
The source of front and rear speaker can be set independently.
As source is choosable:
internal dc coupling (not recommended)
external ac coupling using ACin pins
Figure 17. AC/DC coupling
!#OUT, 37OUT
37IN
!#IN,
LEFTCHANNEL
(IGHPASS
FR
FLAT
6REF
6REF
&RONT&ADER
2E A R&ADER
4.11
RIGHTCHANNEL
2EARSELECTOR
,OWPASS
FR
FLAT
3UBWOOFER &ADER
'!0'03
Front speaker attenuator and mixing
A Mixing-stage is placed after front speaker-attenuator and can be set independently to
mixing-mode. Having a full volume for the Mix-signal the stage offers a wide flexibility to
adapt the mixing levels.
Figure 18. Output selector
&RONT
6OLUME
 D"
D"STEP
(IGHPASS

/UT&
22/37
&ROM-) 8IN
6OLUME
 D"
D"STEP
Doc ID 9837 Rev 2
'!0'03