TDA7402 STMicroelectronics, TDA7402 Datasheet - Page 20

• Manufacturer Part Number: TDA7402
• Description: IC PROCESSOR CAR SIGNAL 44-LQFP
• Manufacturer: STMicroelectronics
• Type: Car Signal Processorr

Specifications of TDA7402

• Applications: Automotive Systems
• Mounting Type: Surface Mount
• Package / Case: 44-LQFP
• Case: QFP
• Dc: 05+
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Audioprocessor part
3.5
Note:
3.6
Note:
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Soft Mute
The digitally controlled Soft Mute stage allows muting/demuting the signal with a I
programmable slope. The mute process can either be activated by the Soft Mute pin or by
the I
regions (see
For timing purposes the Bit0 of the I
until the end of de-muting.
Figure 7.
Please notice that a started mute action is always terminated and could not be interrupted
by a change of the mute -signal.
Soft Step volume
When the volume level is changed audible clicks could appear at the output. The root cause
of those clicks could either be a DC offset before the volume stage or the sudden change of
the envelope of the audio signal. With the Soft Step feature both kinds of clicks could be
reduced to a minimum and are no more audible. The blend time from one step to the next is
programmable in four steps.
Figure 8.
For steps more than 0.5dB the Soft Step mode should be deactivated because it could
generate a hard 1dB step during the blend time.
2
C-bus. This slope is realized in a special S-shaped curve to mute slow in the critical
Soft Mute timing
Soft Step timing
Figure
-0.5dB
0.5dB
-1dB
1dB
7).
V
OUT
+SIGNAL
-SIGNAL
I
2
MUTE
C BUS
EXT.
OUT
REF
1
1
2
C bus output register is set to 1 from the start of muting
SS Time
D97AU634
D00AU1170
Time
Time
2
TDA7402
C bus