TDA7403 Datasheet, PDF (13/26 Pages) STMicroelectronics – BASIC SIGNAL PROCESSOR

Figure 13. Trigger Threshold vs. VPEAK
VTH
TDA7403
MIN. TRIG. THRESHOLD
8 STEPS
65mV
30mV
0.9V
D97AU648
260mV(00)
220mV(01)
180mV(10)
140mV(11)
NOISE CONTROLLED
TRIG. THRESHOLD
1.5V
VPEAK(V)
Figure 14. Deviation Controlled Trigger
Adjustment
Figure 15. Fieldstrength Controlled Trigger
Adjustment
VPEAK
(V_OP)
00
2.8
01
2.0
10
1.2
0.9
DETECTOR OFF (11)
D97AU649
20 32.5
45
75
DEVIATION(KHz)
VPEAK
»3V
MONO
STEREO
NOISE
2.3V(00)
1.8V(01)
1.3V(10)
ATC_SB OFF (11)
noisy signal
D98AU863
good signal
0.9V
E’
Figure 16. Block diagram of the stereo decoder
MPX
100K
INGAIN
3.5 ... 11dB
STEP 2.5dB
D98AU952
INFILTER
LP 80KHz
4.th ORDER
PLL +
PILOT-DET.
F19
F38
STEREO
NOISE BLANKER
HOLDN
DEMODULATOR
- PLOT CANC
- ROLL-OFF COMP.
- LP 25KHz
DEEMPHASIS
+ HIGHCUT
t=50 or 75µs
FM_L
FM_R
SB CONTROL
REF 5V
VSBL
HC
CONTROL
D
A
VHCCH
VHCCL
LEVEL INTERN
LEVEL INPUT
LP 2.2KHZ
1.th ORDER
GAIN 0..10dB
LEVEL
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