TDA7540N Datasheet, PDF (58/76 Pages) STMicroelectronics – AM/FM car radio tuner IC with stereo decoder and intelligent selectivity system (ISS)

Software specification
TDA7540N
Table 36. Addr 24 stereodecoder 1
MSB
LSB
d7 d6 d5 d4 d3 d2 d1 d0
Function
1 only for testing (has to be set to 1)
0
not valid (only for testing)
1
Audio AM noise blanker fix threshold enable
1
0
only for testing (has to be set to 1)
Audio inverter OFF
1
Audio inverter ON
00
Audio noise blanking time 38µs
01
10
Audio noise blanking time 25.5µs
Audio noise blanking time 32µs
11
Audio noise blanking time 22µs
0
Stereodecoder VCO adjust minus
1
Stereodecoder no VCO adjust recommended
0
Stereodecoder VCO adjust plus
1
Stereodecoder no VCO adjustrecommended
Table 37. Addr 25 stereodecoder 2
MSB
LSB
d7 d6 d5 d4 d3 d2 d1 d0
Function
0 Stereo decoder mute disable
1 Stereo decoder mute enable
0
Stereo decoder “ON” if muted
1
Stereo decoder “OFF” if muted
0
Forced MONO, must be set in AM
1
MONO/STEREO switch automatically
0
Noise blanker peak charge current low
1
Noise blanker peak charge current high
0
Pilot threshold high
1
Pilot threshold low
0
Deemphasis 50µs
1
Deemphasis 75µs
00
Stereodecoder ingain = 3.75dB
01
Stereodecoder ingain = 2.5dB
10
Stereodecoder ingain = 1.25dB
11
Stereodecoder ingain = 0dB
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