TDA7421N Datasheet, PDF (36/38 Pages) STMicroelectronics – AM/FM TUNER FOR CAR RADIO AND HI-FI APPLICATIONS

TDA7421N
7.11 TUNER TESTING (subaddress 9H)
MSB
0
0
1
0
1
0
0
1
1
1
0
0
1
1
0
all else not allowed
1
LSB
FUNCTION
AMSSDAC Test
FMSSDAC Test
FMSMDAC Test
FMHDDAC Test
FMIFAGCDAC Test
PLL Test
8.0 COMPONENT DESCRIPTION
CF1
Ceramic filter 10.7MHz, 180KHz BW
CF3-CF4
Ceramic filter 10.7MHz, 150KHz BW
CF2
Ceramic filter 450KHz, 6KHz BW
FM RF transformer
T1
Unloaded Q= 69
3-1= 3 3/4T - 6-4= 3T 0.12f2UEW
CTUNING(3-1)= 26.6pF @ 100MHz
AM/FM IF1 transformer
T2
Unloaded Q= 70
1-3= 12T - 1-5= 6 - 5-3= 6 - 4-6= 2T 0.08f2UEW
CINT(1-3) = 51pF; CEXT(1-3) = 5pF
AM IF2 transformer
T3
Unloaded Q= 40
1-3= 178T - 1-2= 89T - 2-3= 89T - 4-6= 33T 0.05f2UEW
CINT(1-3) = 180pF; CEXT(1-3) = 20pF
Oscillator coil
L2
Unloaded Q= 8
06-4= 2 1/2T 0.12f2UEW
CTUNING(6-4)= 36.8pF @ 100MHz
Demodulator Coil
L6
Unloaded Q= 35
6-4= 27T 0.1f2UEW
CINT(4-6)= 47pF; CEXT(4-6) = 13.5pF
AM BPF RC
2.7K
27nF
D98AU915
18nF
100K
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