TDA7719
Description
Figure 3.
QD and FD configuration of QD4/FD4
FULL DIFFERENTIAL
QUASI DIFFERENTIAL
1
FD4L+
1
QD4L
QD4G
QD4G
QD4R
100k
100k
+
-
+
-
OUTL
OUTL
FD4L-
2
1
2
1
100k
100k
100k
100k
FD4R+
+
-
+
-
OUTR
OUTR
FD4R-
2
2
100k
100k
4.2
Mixing
The device provides mixing function which allows the mixing source mixed into front and
rear speaker output independently. The mixing source can be any single-ended input,
mono-differential input or beep input (Mono single-ended input when DC offset detector is
not used). In order to adjust the level of mixing signal, the mixing selector is followed with a
0dB~-31dB attenuator. The maximum mixing input signal level is 1.6Vrms for single-ended
input and mono-differential input. For beep input, the maximum input signal level is about
1.4Vrms. The block diagram of the mixing function is shown below.
Figure 4.
Block diagram of mixing stage
SE Inputs
MD Inputs
Beep
Mixing
Selector
0~-31dB
Speaker
Attenuator
15/45
STMICROELECTRONICS [ ST ]
