TDA7406 Datasheet, PDF (31/64 Pages) STMicroelectronics – Car radio signal processor

TDA7406
6
Noise blanker part
Noise blanker part
6.1
Features:
● AM and FM mode
● internal 2nd order 140kHz high-pass filter for MPX path
● internal rectifier and filters for AM-IF path
● programmable trigger thresholds
● trigger threshold dependent on high frequency noise with programmable gain
● additional circuits for deviation- and fieldstrength-dependent trigger adjustment
● 4 selectable pulse suppression times for each mode
● programmable noise rectifier charge/discharge current
6.2
Noise blanker electrical characteristics
Table 6.
Noise blanker electrical characteristics
All parameters measured in FM mode if not otherwise specified.
Symbol
Parameter
Test conditions
Min. Typ.
111
30
110
35
101
40
V_TR Trigger Threshold⁽¹⁾
noise controlled
V_{TRNOISE Trigger Threshold}
V_RECT Rectifier Voltage
Deviation dependent
V_{RECTDEV Rectifier Voltage}
meas.with
100
V_PEAK=0.9V
011
010
001
000
00
meas.with
01
V_PEAK=1.5V
10
11
V_MPX=0mV
V_MPX=50mV, f=150kHz
V_MPX=200mV, f=150kHz
11
meas.with
10
V_MPX=500mV
01
(75kHz dev.)
00
45
50
55
60
65
260
220
180
140
0.5
0.9
1.5
1.7
2
2.5
0.5 0.9 (off)
0.9
1.2
1.7
2.0
2.5
2.8
Max.
1.3
2.1
2.9
1.3
1.5
2.3
3.1
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
V_OP
V_OP
V_OP
V_OP
31/64