TDA7402_07 STMICROELECTRONICS [STMicroelectronics], TDA7402_07 Datasheet - Page 21

• Manufacturer Part Number: TDA7402_07
• Description: Car radio signal processor
• Manufacturer: STMICROELECTRONICS [STMicroelectronics]

TDA7402
4.4
Note:
4.5
SoftMute
The digitally controlled SoftMute stage allows muting/demuting the signal with a I
programmable slope. The mute process can either be activated by the SoftMute 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.
SoftStep 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 audiosignal. With the SoftStep 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.
2
C-bus. This slope is realized in a special S-shaped curve to mute slow in the critical
Softmute timing
SoftStep timing
Figure
-0.5dB
0.5dB
-1dB
1dB
V
7).
OUT
+SIGNAL
-SIGNAL
I
2
MUTE
EXT.
C BUS
OUT
REF
1
1
2
C bus output register is set to 1 from the start of muting
SS Time
D97AU634
D00AU1170
Time
Audioprocessor part
Time
2
C bus
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