TDA7703 Datasheet, PDF (24/32 Pages) STMicroelectronics – Automatic self alignment for image rejection

Weak signal processing
5
Weak signal processing
TDA7703
All the parameters in this section refer to the programmability of the DSP part of the device.
The typical values are those set by default parameters (start-up without parametric change
from main µP); the max and the min values refer to the programmability range. The values
are referred to the typical application. Wherever the possible values are a discrete set, all
the possible programmable values are displayed.
5.1
FM IF-processing
5.1.1 Dynamic channel selection filter (DISS)
Table 19. Dynamic channel selection filter (DISS)
(discrete set)
Symbol
Parameter
Test condition
Min
IF filter #2
-
DISS BW IF filter #1
response: - 3dB
-
IF filter #0
-
5.1.2 Soft mute
Table 20. Soft mute
(continuous set)
Symbol
Parameter
Test condition
Min
audio atten = 1 dB
SMsp Start point vs. field strength read “FM_softmute”
0
no adjacent channel present
audio atten = SMd + 1 dB
SMep End point vs. field strength read “FM_softmute”
-6
no adjacent channel present
SMd Depth
-30
Field strength LPF cut-off
SMtauatt frequency for soft mute
0.1
activation
Field strength LPF cut-off
SMtaurel frequency for soft mute
0.1
release
Typ Max Units
±80
-
kHz
±60
-
kHz
±40
-
kHz
Typ Max Units
6
20 dBµV
-6
10 dBµV
-15
0
dB
100 4000 Hz
1
4000 Hz
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