TDA7412 Datasheet, PDF (15/56 Pages) STMicroelectronics – CARRADIO SIGNAL PROCESSOR

TDA7412
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
V_OUT
1dB
0.5dB
-0.5dB
SS Time
Time
-1dB
D00AU1170
Note:
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.
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_C = 80Hz, Q = 1
15.0
10.0
5.0
dB
0.0
-5.0
-10.0
-15.0
10.0
100.0
Hz
1.0K
10.0K
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