TDA7412 ST Microelectronics, TDA7412 Datasheet - Page 15

• Manufacturer Part Number: TDA7412
• Description: CARRADIO SIGNAL PROCESSOR
• Manufacturer: ST Microelectronics

1.6 SoftStep-Volume and Speaker
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 6. SoftStep-Timing
Note:
1.7 Bass
There are four parameters programmable in the bass stage:
1.7.1 Attenuation
Figure 7 shows the attenuation as a function of frequency at a center frequency of 80Hz.
Figure 7. Bass Control @ f
For steps more than 0.5dB (Volume) /1dB (speaker) the SoftStep mode should be deactivated because it could generate a hard
1dB step during the blend-time.
dB
-10.0
-15.0
15.0
10.0
-5.0
5.0
0.0
10.0
-0.5dB
0.5dB
-1dB
1dB
V
OUT
C
= 80Hz, Q = 1
100.0
SS Time
Hz
1.0K
D00AU1170
Time
10.0K
TDA7412
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