TDA7402 Datasheet, PDF (28/59 Pages) STMicroelectronics – CARRADIO SIGNAL PROCESSOR

TDA7402
2.3.4 ACI ( Adjacent Channel Interference )
α114 = _V----^V_O-----^O₍--_s--⁽--_ps---_u-ⁱ--^g-_r---ⁿⁱ--_o-^a--_u--^l--⁾_s--⁽--₎-^a--₍--^ta--¹--_t--^k4---^H-_k---_H-^z---⁾-_z--₎-;f_s = 110k Hz – (3 ⋅ 38kH z)
α190 = _V----^V_O-----^O₍--_s--⁽--_ps---_u-ⁱ--^g-_r---ⁿⁱ--_o-^a--_u--^l--⁾_s--⁽--₎-^a--₍--^ta--¹--_t--^k4---^H-_k---_H-^z---⁾-_z--₎-;f_s = 186k Hz – (5 ⋅ 38kH z)
measured with: 90% mono signal; 9% pilot signal; fm=1kHz; 1% spurious signal ( f_S = 110kHz or 186kHz, un-
modulated).
2.4 NOISE BLANKER PART
2.4.1 Features:
s AM and FM mode
s internal 2nd order 140kHz high-pass filter for MPX path
s internal rectifier and filters for AM-IF path
s programmable trigger thresholds
s trigger threshold dependent on high frequency noise with programmable gain
s additional circuits for deviation- and fieldstrength-dependent trigger adjustment
s 4 selectable pulse suppression times for each mode
s programmable noise rectifier charge/discharge current
2.4.2 ELECTRICAL CHARACTERISTICS
All parameters measured in FM mode if not otherwise specified.
Symbol
Parameter
Test Condition
V_{TR Trigger Threshold} ¹⁾
meas.with
111
V_PEAK=0.9V
110
101
100
011
010
001
000
V_TRNOISE noise controlled
Trigger Threshold
meas.with
00
V_PEAK=1.5V
01
10
11
V_RECT Rectifier Voltage
V_MPX=0mV
V_MPX=50mV, f=150kHz
V_MPX=200mV, f=150kHz
Min.
Typ.
30
35
40
45
50
55
60
65
260
220
180
140
0.9
1.7
3.5
Max.
Unit
mV_OP
mV_OP
mV_OP
mV_OP
mV_OP
mV_OP
mV_OP
mV_OP
mV_OP
mV_OP
mV_OP
mV_OP
V
V
V
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