TDA7412 Datasheet, PDF (33/56 Pages) STMicroelectronics – CARRADIO SIGNAL PROCESSOR

Figure 26. Internal stereoblend characteristics
TDA7412
The gain can be programmed through 4 bits in the "Stereodecoder-Adjustment"-byte. All necessary internal ref-
erence voltages like REF5V are derived from a bandgap circuit. Therefore they have a temperature coefficient
near zero.
Figure 27. Relation between internal and external LEVEL-voltages for setup of Stereoblend
INTERNAL
VOLTAGES
REF 5V
VSBL
SETUP OF VST
LEVEL INTERN
INTERNAL
VOLTAGES
REF 5V
LEVEL
70%
VSBL
20%
SETUP OF VMO
LEVEL INTERN
VMO
VST
t
FIELDSTRENGHT VOLTAGE
VMO
D00AU1168
t
VST
FIELDSTRENGHT VOLTAGE
3.9 Highcut Control
The highcut control set-up is similar to the stereoblend control set-up : the starting point VHCH can be set with
2 bits to be 42, 50, 58 or 66% of REF5V whereas the range can be set to be 17, 22, 28 or 33% of VHCH (see
fig. 30).
Figure 28. Highcut characteristics
LOWPASS
TIME CONSTANT
3.7•τ_'Deemp
3•τ_Deemp
DEEMPHASIS SHIFT ON
OFF
τ_Deemp
τ_'Deemp
D00AU1169
VHCL
VHCH
FIELDSTRENGHT
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