TDA7460N Datasheet, PDF (9/31 Pages) STMicroelectronics – CAR RADIO SIGNAL PROCESSOR

TDA7460N
Figure 2. Input stages
CD
CDGND
PHONE
100K
PH_GND
CASSETTE
AM
MPX
100K
100K
100K
15K
15K
15K
15K
15K
-
+
15K
15K
-
+
15K
STEREODECODER
IN GAIN
D97AU633A
Mixing Stage
This stage offers the possibility to mix the internal
beep or the phone signal to any other source.
Due to the fact that the mixing stage is also lo-
cated behind the In-Gain stage fine adjustments
of the main source level can be done in this way.
Loudness
There are four parameters programmable in the
loudness stage (see fig. 3, 4, 5):
Figure 3. Loudness Attenuation @ fc = 400Hz
(second order)
0.0
-5.0
-10.0
-15.0
- Attenuation
- Center Frequency
- Loudness Q
- Flat Mode: in this mode the loudness stage works
as a 0 - 15dB attenuator.
Softmute
The digitally controlled softmute stage allows
muting/demuting the signal with a I²C bus pro-
grammable slope. The mute process can either
be activated by the softmute pin or by the I²C
bus. The slope is realized in a special S shaped
curve to mute slow in the critical regions (see fig-
ure 6).
For timing purposes the Bit 3 of the I²C bus out-
put register is set to 1 from the start of muting un-
til the end of demuting.
-20.0
10.0
100.0
1.0K
10.0K
Figure 4. Loudness Center frequency @ Attn.
= 15dB (second order)
0.0
-5.0
-10.0
-15.0
-20.0
10.0
100.0
1.0K
10.0K
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