STMICROELECTRONICS TDA7541B

TDA7541B
AM/FM car radio tuner IC with stereo decoder
and intelligent selectivity system
Features
■
FM part
– AGC generation by RF and IF detection
– I/Q mixer for 1st IF 10.7 MHz with image
rejection
– Mixer for 2nd IF 450 kHz
– Internal 450 kHz band pass filter with
bandwidth control by ISS
– Fully integrated FM demodulator with noise
cancellation
■
AM part
– Wide and narrow AGC generation
– Mixer for 1st IF 10.7 MHz, AM up
conversion
– Mixer for 2nd IF 450 kHz
– Integrated AM-demodulator
– AM IF noise blanking
■
Stereo decoder
– PLL with adjustment free, fully integrated
VCO
– Automatic pilot dependent
MONO/STEREO switching
– Programmable ROLL-OFF compensation
– High cut and stereo blend-characteristics
programmable
– Dedicated RDS mute
– Audio noise blanker
■
Additional features
– VCO for world tuning range
Table 1.
July 2009
LQFP64
– High performance fast PLL for RDSSystem
– IF counter for FM and AM with search stop
signal
– Quality detector for level, deviation,
adjacent channel and multipath
– ISS (Intelligent selectivity system) for
cancellation of adjacent channel and noise
influences
– Adjacent channel mute
– Fully electronic alignment
– Independent weather band input
– All functions I2C bus controlled
Description
The TDA7541B is a high performance tuner
circuit with stereo decoder for AM/FM car radio. It
contains a mixer, IF amplifier, demodulator for AM
and FM, stereo decoder, quality detection, ISS
filter and PLL synthesizer with IF counter on a
single chip. Use of BICMOS technology allows the
implementation of several tuning functions and a
minimum of external components.
Device summary
Order code
Package
Packing
TDA7541B
LQFP64 (10 x 10 x 1.4 mm)
Tray
TDA7541BTR
LQFP64 (10 x 10 x 1.4 mm)
Tape and reel
TDA7541BW
LQFP64 (14 x 14 x 1.4 mm)
Tray
TDA7541BWTR
LQFP64 (14 x 14 x 1.4 mm)
Tape and reel
Doc ID 16048 Rev 1
1/77
www.st.com
1
Contents
TDA7541B
Contents
1
Block circuit diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2
Pin connection and pin description . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
3
4
2.1
Pin connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2.2
Pin description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Electrical specifications and characteristics . . . . . . . . . . . . . . . . . . . . 10
3.1
Thermal data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
3.2
Absolute maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
3.3
Electrical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
3.3.1
Globals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
3.3.2
FM section . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
3.3.3
AM section . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
3.3.4
Stereo decoder section . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
3.3.5
PLL section . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Functional description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
4.1
4.2
FM part . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
4.1.1
Mixer 1 AGC and IF amplifier . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
4.1.2
Mixer2, limiter, FM demodulator and spike cancellation . . . . . . . . . . . . 26
4.1.3
Quality detection and ISS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
4.1.4
Block diagram quality detection principle . . . . . . . . . . . . . . . . . . . . . . . . 29
4.1.5
Strong adjacent channel correction . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
4.1.6
Weak signal mute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
4.1.7
Weather band input . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
AM section . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
4.2.1
4.3
4.4
2/77
Usage of control bit ADSEL (Addr23D7) . . . . . . . . . . . . . . . . . . . . . . . . 32
Stereo decoder . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
4.3.1
Decoder . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
4.3.2
Noise blanker . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
4.3.3
Functional description of the multipath detector . . . . . . . . . . . . . . . . . . 37
4.3.4
Quality detector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
4.3.5
AFS control and stereo decoder mute . . . . . . . . . . . . . . . . . . . . . . . . . . 37
PLL and IF counter section . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Doc ID 16048 Rev 1
TDA7541B
Contents
4.5
5
4.4.1
PLL frequency synthesizer block . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
4.4.2
IF counter block . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
I2C
bus interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Software specification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
5.1
Chip address and overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
5.2
Address organization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
5.3
Control register function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
5.4
Data byte specification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
6
Appendix . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68
7
Application circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
8
Package information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75
9
Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76
Doc ID 16048 Rev 1
3/77
List of tables
TDA7541B
List of tables
Table 1.
Table 2.
Table 3.
Table 4.
Table 5.
Table 6.
Table 7.
Table 8.
Table 9.
Table 10.
Table 11.
Table 12.
Table 13.
Table 14.
Table 15.
Table 16.
Table 17.
Table 18.
Table 19.
Table 20.
Table 21.
Table 22.
Table 23.
Table 24.
Table 25.
Table 26.
Table 27.
Table 28.
Table 29.
Table 30.
Table 31.
Table 32.
Table 33.
Table 34.
Table 35.
Table 36.
Table 37.
Table 38.
Table 39.
Table 40.
Table 41.
Table 42.
Table 43.
4/77
Device summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Pin description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Thermal data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Absolute maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Globals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
FM section . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
AM section . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Stereo decoder section . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
PLL section . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
ISS filter control by I2C bus. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Internal ISS control signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
ISS control modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Usage of ADSEL. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
Address organization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
I2C control bit description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
Subaddress description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Addr 0 TPLL charge pump control (0Bh) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Addr 1 TPLL Counter 1 (LSB). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
Addr 2 TPLL Counter 2 (MSB) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
Addr 3 TV(00h) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
Addr 4 TV/IF Counter (FM ACh, AM 1Ch) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
Addr 5 TPLL Divider (FM 3Dh, AM 2Dh) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
Addr 6 AGC (FM 06h, AM 2Ah) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
Addr 7 Quality AC (FM 50h) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
Addr 8 Quality ACM/MP (FM 6Ah) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
Addr 9 Quality Dev (FM 49h) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
Addr 10 Quality MUX/FSU (FM 0Eh, AM 0Fh) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
Addr 11 Weak Signal Mute (FM A8h) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
Addr 12 AM IF NB (AM B1h) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
Addr 13 XTAL adjust(80h) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
Addr 14 IF2 adjust (FM E8h, AM 08h) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
Addr 15 IQ adjust / Switch (FM E7h) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
Addr 16 FM keying AGC (FM 1Dh). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
Addr 17 Roll off / Level gain (77h) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
Addr 18 SD Stereoblend / AM corner frequency (0Dh) . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
Addr 19 SD High cut (2Fh) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
Addr 20 SD MP (FM 97h, AM 3Fh). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
Addr 21 SD Quality (FFM 7Ah, AM FAh) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
Addr 22 SD NB I (FM 05h, AM 04h) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
Addr 23 SD NB II (FM E2h, AM C2h) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
Addr 24, 26, 27, 28, 29 testing (FEh) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
Addr 25 Testing (FEh) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
Document revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76
Doc ID 16048 Rev 1
TDA7541B
List of figures
List of figures
Figure 1.
Figure 2.
Figure 3.
Figure 4.
Figure 5.
Figure 6.
Figure 7.
Figure 8.
Figure 9.
Figure 10.
Figure 11.
Figure 12.
Figure 13.
Figure 14.
Figure 15.
Figure 16.
Block circuit diagram. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Pin connection (top view) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Programming of HC filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Programming of stereo blend . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Adaptive threshold control of noise blanker . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Stereo blend controlled threshold adjust . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Deviation controlled threshold adjust . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Block diagram FM part . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68
Block diagram VCO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
Block diagram ISS function. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
Block diagram AM path. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
Block diagram stereo decoder . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72
Block diagram audio noise blanker . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72
Block diagram multi path detection for stereo decoder. . . . . . . . . . . . . . . . . . . . . . . . . . . . 73
Application circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
LQFP64 mechanical data and package dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75
Doc ID 16048 Rev 1
5/77
Block circuit diagram
1
Block circuit diagram
Figure 1.
6/77
TDA7541B
Block circuit diagram
Doc ID 16048 Rev 1
TDA7541B
Pin connection and pin description
2
Pin connection and pin description
2.1
Pin connection
GNDVCC2
MIX2AMPOUT
VCC2
MIX2REF
MIX2OUT
AMRFAGCTC
MIX2INREF
MIX2IN
AMAGC2TC
IF1REF
IF1AMPOUT
VCCIF1
IF1AMPIN
GNDIF
MIX1REF
Pin connection (top view)
MIX1OUT
Figure 2.
64 63 62 61 60 59 58 57 56 55 54 53 52 51 50 49
48
VREF1
2
47
AMIF2IN
AMMIX1IN
3
46
GNDDEM
AMRFAGCOUT
4
45
FMREFDEMC
WB
5
44
AMIF2REF
AMMIX1RAF
6
43
MPXOUT
AMPINDR
7
42
MUTETC
FMMIX1IN1
8
41
MPXIN
GNDRF
9
40
AMREFDEMC
FMMIX1IN2
10
39
MPTC
TV
11
38
GNDSTD
FMPINDR
12
37
FSWO
FMAGCTC
13
36
VCC1
VCOB
14
35
R
VCOE
15
34
L
VCCVCO
16
33
GNDVCC1
Doc ID 16048 Rev 1
XTALD
ISSTC2
ISSTC1
XTALG
FSTC
FSU
SCL
SDA
SSTOP
SW
LPF
LPHC
VREF2
23 24 25 26 27 28 29 30 31 32
LPOUT
17 18 19 20 21 22
MUX
1
DEVTC
GNDVCO
VCCMIX1
7/77
Pin connection and pin description
2.2
Pin description
Table 2.
Pin description
Pin No.
8/77
TDA7541B
Pin name
Function
1
VCCMIX1
Mixer1 Supply
2
DEVTC
Deviation Detector Time Constant
3
AMMIX1IN
AM Mixer1 Input
4
AMRFAGCOUT
AM RF AGC Voltage Output
5
WB
Weather Band Input
6
AMMIX1REF
AM Mixer1 Reference
7
AMPINDR
AM Pin Diode Driver Output
8
FMMIX1IN1
FM Mixer1 Input1
9
GNDRF
RF Ground
10
FMMIX1IN2
FM Mixer1 Input2
11
TV
Tuning Voltage Preselection
12
FMPINDR
FM Pin Diode Driver Output
13
FMAGCTC
FM AGC Time Constant
14
VCOB
VCO Input Base
15
VCOE
VCO Output Emitter
16
VCCVCO
VCO Supply
17
GNDVCO
VCO Ground
18
LPOUT
OpAmp Output to PLL Loop Filter
19
VREF2
Voltage Reference for PLL OpAmp
20
LPF
OpAmp Input to PLL Loop Filter
21
LPHC
High Current PLL Loop Filter Input
22
SW
Free Programmable Switch Output
23
MUX
Multiplexer Output
24
SSTOP
Search Stop Output
25
SDA
I2C Bus Data
26
SCL
I2C Bus Clock
27
FSU
Unweighted Field Strength Output
28
FSTC
S-meter Filtering Capacitor
29
XTALG
Xtal Oscillator to MOS Gate
30
ISSTC1
ISS Filter Time Constant1 (slow)
31
ISSTC2
ISS Filter Time Constant2 (fast)
32
XTALD
Xtal Oscillator to MOS Drain
33
GNDVCC1
Digital Ground
Doc ID 16048 Rev 1
TDA7541B
Pin connection and pin description
Table 2.
Pin description (continued)
Pin No.
Pin name
Function
34
L
Stereo Decoder Output Left
35
R
Stereo Decoder Output Right
36
VCC1
Digital Supply
37
FSWO
Weighted Field Strength Output
38
GNDSTD
Stereo Decoder Ground
39
MPTC
Multipath Detector Time Constant
40
AMREFDEMC
AM Demodulator Reference
41
MPXIN
Stereo Decoder Input
42
MUTETC
Weak Signal Mute Time Constant
43
MPXOUT
AM Audio / MPX Output
44
AMIF2REF
AM IF2 Amplifier Reference Voltage
45
FMREFDEMC
FM Demodulator Reference
46
GNDDEM
FM Demodulator Ground
47
AMIF2IN
AM IF2 Amplifier Input
48
VREF1
5V Reference
49
GNDVCC2
Analog Ground
50
MIX2AMPOUT
MIXER2 Amplifier Output
51
VCC2
Analog Supply
52
MIX2REF
Mixer2 Reference
53
MIX2OUT
Mixer2 Output
54
AMRFAGCTC
AM RF AGC Time Constant
55
MIX2INREF
Mixer2 Input Reference
56
MIX2IN
Mixer2 Input
57
AMAGC2TC
AM AGC2 Time Constant
58
IF1REF
IF1 Amplifier Reference
59
IF1AMPOUT
IF1 Amplifier Output
60
VCCIF1
IF1 Supply
61
IF1AMPIN
IF1 Amplifier Input
62
GNDIF1
IF1 Ground
63
MIX1REF
Mixer1 Reference
64
MIX1OUT
Mixer1 Output
Doc ID 16048 Rev 1
9/77
Electrical specifications and characteristics
TDA7541B
3
Electrical specifications and characteristics
3.1
Thermal data
Table 3.
Thermal data
Symbol
Parameter
RTH(j-amb) Thermal resistance junction-to-ambient
3.2
Max.
Value
Unit
70
°C/W
Absolute maximum ratings
Table 4.
Absolute maximum ratings
Symbol
Parameter
Conditions
Value
Unit
Supply voltage
-
9.5
V
Tamb
Ambient temperature
-
-40 to 85
°C
Tstg
Storage temperature
-
-55 to +150
°C
2
kV
Machine Model
100
V
Charged Device Model
300
V
VS
Human Body Model
VESD
ESD withstand voltage
3.3
Electrical characteristics
3.3.1
Globals
Tamb = 25 °C, VCC1 = VCC2 = VCCMIX1 = VCCVCO = VCCIF = 8.5 V, fXtal = 10.25 MHz,
in application circuit, unless otherwise specified.
Table 5.
Item
Globals
Symbol
Parameter
Test conditions
Min.
Typ.
Max.
Unit
1. Supply
1.1
VCC1
Digital supply voltage
-
7.7
8.5
9
V
1.2
VCC2
Analog supply voltage
-
7.7
8.5
9
V
1.3
VCCVCO
VCO supply voltage
-
7.7
8.5
9
V
1.4
VCCMIX1
Mixer1 supply voltage
-
7.7
8.5
9
V
1.5
VCCIF
IF1 Supply Voltage
-
7.7
8.5
9
V
1.6
ICC1
Supply current
FM ON
-
19
23
mA
1.7
ICC1
Supply current
AM ON
-
21
25
mA
1.8
ICC2
Supply current
FM ON
-
48
58
mA
1.9
ICC2
Supply current
AM ON
-
37
44
mA
10/77
Doc ID 16048 Rev 1
TDA7541B
Table 5.
Item
Electrical specifications and characteristics
Globals (continued)
Symbol
Parameter
Test conditions
Min.
Typ.
Max.
Unit
1.10
ICCVCO
Supply current
-
-
12
15
mA
1.11
ICCMIX1
Supply current
FM ON
-
32
40
mA
1.12
ICCMIX1
Supply current
AM ON
-
20
24
mA
1.13
ICCIF
Supply current
-
-
4
5
mA
2. Reference voltages
2.1
VREF1
Internal reference voltage
IREF1 = 0mA
4.8
5
5.2
V
2.2
VREF2
Internal reference voltage
IREF2 = 0mA
2.4
2.5
2.6
V
3. I2C bus interface
3.1
fSCL
Clock frequency
-
-
-
400
kHz
3.2
VIL
Input low voltage
-
-
-
1
V
3.3
VIH
Input high voltage
-
2
-
-
V
3.4
IIN
Input current
-
-5
-
5
µA
3.5
VO
Output acknowledge voltage
IO = 1.6mA
-
-
0.4
V
3.3.2
FM section
Tamb = 25 °C, VCC1 = VCC2 = VCCMIX1 = VCCVCO = VCCIF = 8.5 V, fXtal = 10.25 MHz,
fRF = 98 MHz, dev = 40 kHz, fMod = 1 kHz, in application circuit, unless otherwise specified.
Table 6.
Item
FM section
Symbol
Parameter
Test conditions
Min.
Typ.
Max.
Unit
4. Wide band RF AGC
4.1
V8-10
Lower threshold start
V13 = 2.5 V, RFK “0”
-
79
-
dBμV
4.2
V8-10
Upper threshold start
V13 = 2.5 V, RFK”0”
-
93
-
dBμV
4.3
Δ V8-10
Control range RF KAGC
KAGC”000”, RFAGC”00”,
V37 = 3.0….3.7 V, RFK”1”
5
8
11
-
5. Narrow band IF and keying AGC
5.1
V61
Lower threshold start
KAGC = off, V8-10 = 0 mVRMS
-
82
-
dBµV
5.2
V61
Upper threshold start
KAGC = off, V8-10 = 0 mVRMS
-
94
-
dBµV
5.3
V61
Max. IFAGC threshold
with KAGC
KAGC”000”,IFAGC”00”,
V37 = 3.0 V
-
97
-
dBµV
5.4
V37
Start point KAGC
KAGC”000”,IFAGC”00”,
3.2
3.4
3.6
V
5.5
Δ V61
Control range IF KAGC
KAGC”000”,IFAGC”00”,
V37 = 3.2….3.9 V
12
15
18
dB
-
-
VREF1
+VBE
V
6. AGC time constant output
6.1
V13
Max. AGC output voltage
V8-10= 0 mVRMS
Doc ID 16048 Rev 1
11/77
Electrical specifications and characteristics
Table 6.
TDA7541B
FM section (continued)
Item
Symbol
Parameter
Test conditions
Min.
Typ.
Max.
Unit
6.2
V13
Min. AGC output voltage
V8-10 = 100 mVRMS
-
-
0.5
V
6.3
I13
Min. AGC charge current
V8-10= 0 mVRMS,V13 = 2.5 V
-33
-25
-17.5
µA
6.4
I13
Max. AGC discharge
current
V8-10 = 100 mVRMS,V13 = 2.5 V
1.7
2.5
3.3
mA
15
25
35
µA
7. AGC PIN diode driver output
7.1
I12
AGC OUT, current min.
V8-10 = 0 mVRMS, V12 = 2.5V
7.2
I12
AGC OUT, current max.
V8-10 = 50 mVRMS, V12 = 2.5 V
-
-
-16
mA
8. FM I/Q Mixer1 (10.7 MHz)
8.1
RIN
Input resistance
Differential
8
10
12
kΩ
8.2
CIN
Input capacitance
Differential
-
4
-
pF
8.3
ROUT
Output resistance
-
530
660
790
Ω
8.4
V8,11
Input DC bias
-
2.2
2.5
2.8
V
8.5
G
Gain
Unloaded
20
22
24
dB
8.6
Gl
Gain
With 330 Ω load
14
16
18
dB
8.7
INOISE
Equivalent input noise
-
-
3
-
nV/√Hz
8.8
CP1dB
1dB compression point
Referred to diff. mixer input
-
100
-
dBµV
rd
8.9
IIP3
3 order intermodulation
-
-
119
-
dBµV
8.10
IQP
I/Q phase adjust
PH
-7
-
+8
DEG
8.11
IRR
Image rejection ratio
Ratio wanted/image
30
40
-
dB
8.12
IRR
Image rejection ratio
With phase adjust
40
46
-
dB
9. WB I/Q Mixer1 (10.7 MHz)
9.1
RIN
Input resistance
Single ended
1.7
2.5
3.3
kΩ
9.2
CIN
Input capacitance
Single ended
-
3
-
kΩ
9.3
ROUT
Output resistance
-
530
660
790
Ω
9.4
V5
Input dc bias
-
2
2.3
2.6
V
9.5
G
Gain
unloaded
24
26
28
dB
9.6
INOISE
Equivalent Input noise
Source impedance 400 Ω
-
2.3
-
nV/√Hz
9.7
IIP3
3rd order intermodulation
-
-
113
-
dBµV
10. IF1 amplifier (10.7 MHz)
10.1
RIN
Input resistance
-
265
330
396
Ω
10.2
CIN
Input capacitance
-
-
2.5
-
pF
10.3
V61
DC input voltage
-
-
VCCIF1/3
-
V
10.4
ROUT
Output resistance
-
265
330
396
Ω
10.5
COUT
Output capacitance
-
-
2.5
-
pF
12/77
Doc ID 16048 Rev 1
TDA7541B
Table 6.
Electrical specifications and characteristics
FM section (continued)
Item
Symbol
10.6
V59
DC output voltage
10.7
Gmin
10.8
Gmax
10.9
10.10
10.11
Min.
Typ.
Max.
Unit
-
-
VCCIF1/2
-
V
Min. gain
IFG
-
9
-
dB
Max. gain
IFG
-
21
-
dB
INOISE
Equivalent input noise
voltage
Gmax, Rgen=330 Ω, RL=330 Ω,
noise of Rgen not included
-
3.2
-
nV/√Hz
CP1dB
1 dB compression point
referred to 330 Ω input, Gmax
-
99
-
dBµV
3rd
referred to 330 Ω input, Gmax
-
130
-
dBµV
240
300
360
Ω
IIP3
Parameter
order Intermodulation
Test conditions
11. Mixer2 (450kHz)
11.1
RIN
Input resistance
Differential
11.2
CIN
Input capacitance
-
-
2.5
-
pF
11.3
V55.56
DC input voltage
-
3.7
4
4.3
V
11.4
ROUT
Output resistance
-
100
-
-
kΩ
11.5
COUT
Output capacitance
-
-
2.5
-
pF
11.6
V52,53
DC output voltage
-
3.7
4
4.3
V
11.7
gm
Conversion
transconductance
WB Mode; referred to MIX2OUT
-
126
-
µA/V
11.8
G
Gain
FM Mode, referred to MIX2OUT
-
16
-
dB
11.9
Cstep
Min. cap. Step
IF2A
-
2.2
-
pF
11.10
Cmax
Max. cap.
IF2A
-
33
-
pF
11.11
INOISE
Equivalent input noise
voltage,
including buffer mixer2
Rgen = 330 Ω, IF2Q”10”
noise of Rgen not included
-
15
-
nV/√Hz
11.12
CP1dB
1dB compression point
referred to 330 Ω input,IF2Q”10”
-
116
-
dBμV
3rd
referred to 330 Ω input,IF2Q”10”
-
132
-
dBμV
-
0.1
0.3
%
11.13
IIP3
order Intermodulation
12. Demodulator, audio output
12.1
THD
Total harmonic distortion
Dev.= 75 kHz, V56= 100 dBµV,
IF2Q”11”
12.2
aAM
AM suppression
V56 =100 dBµ, Δf = 40 KHz,
fmod =1 kHz,
fmod =1 kHz@AM, m =0.3 %
40
60
-
dB
12.3
VMPX
MPX output signal
Dev.= 75 kHz
440
500
560
mVRMS
12.4
ROUT
Output impedance
-
20
40
60
Ω
12.5
RLOAD
Load resistance
-
10
-
-
kΩ
Doc ID 16048 Rev 1
13/77
Electrical specifications and characteristics
Table 6.
Item
TDA7541B
FM section (continued)
Symbol
Parameter
Test conditions
Min.
Typ.
Max.
Unit
70
-
-
dB
40
-
-
dB
Δf = 40 kHz, fmod =1 kHz,
12.6
12.7
(S+N)/N
(S+N)/N
V56 =100 dBµV,
Signal plus noise-to-noise De-emphasis = 50 µs,
ratio at MPXOUT
B = 200 Hz to 15 kHz
ISSENA = 0
Δf = 3.5 kHz, fmod =1 kHz,
Signal plus noise-to-noise
V56 =100 dBµV,
ratio
De-emphasis = 75 µs,
In weatherband mode
setting see Table 10
13. Quality detection
Unweighted field strength (FSU) and weighted field strength
13.1
V37
DC output voltage
V56 = 20 dBμV, FMON=1,
FSWO = OFF
-
2.5
-
V
13.2
V37
DC output voltage
V56 = 50 dBμV, FMON=1,
FSWO = OFF
-
3
-
V
13.3
V37
DC output voltage
V56 = 70 dBμV, FMON=1,
FSWO = OFF
-
3.5
-
V
13.4
V37
DC output voltage
V56 > 120 dBμV, FMON=1,
FSWO = OFF
-
4.6
-
V
13.5
ΔV37
Slope
-
-
25
-
mV/dB
13.6
ΔV37
DC offset
-
-200
-
0
mV
13.7
ROUT
Output impedance
FSWO
17
23.5
30
kΩ
13.8
V27
DC output voltage
V56 = 20 dBμV, FMON=1,
SL=”101”
-
0.1
0.4
V
13.9
V27
DC output voltage
V56 = 50 dBμV, FMON=1,
SL=”101”
-
1
-
V
13.10
V27
DC output voltage
V56 = 70 dBμV, FMON=1,
SL=”101”
-
2
-
V
13.11
V27
DC output voltage
V56 > 120 dBμV, FMON=1,
SL=”101”
4
-
-
V
13.12
ΔV27
Slope
-
-
50
-
mV/dB
13.13
ROUT
Output impedance
FSU
320
400
480
Ω
13.14
Rload
Load resistor
FSU
-
20
-
kΩ
13.15
V27
DC output voltage AM
V47 = 20 dBμV, FMON = 0,
SL= ”010”
-
0.1
0.3
V
13.16
V27
DC output voltage AM
V47 = 40 dBμV, FMON = 0,
SL= ”010”
-
1.25
-
V
13.17
V27
DC output voltage AM
V47 = 60 dBμV, FMON = 0,
SL= ”010”
-
3.0
-
V
13.18
V27
DC output voltage AM
V47 > 100 dBμV, FMON = 0,
SL= ”010”
4.5
-
-
V
14/77
Doc ID 16048 Rev 1
TDA7541B
Table 6.
Electrical specifications and characteristics
FM section (continued)
Item
Symbol
13.19
ΔV27
13.20
fLP
Parameter
Test conditions
Min.
Typ.
Max.
Unit
Slope AM
FMON=0
-
90
-
mV/dB
-3 dB frequency low pass
AM
FMON=0
-
40
-
kHz
-
-
32
-
dB
-3 dB frequency highpass
ACF=0
-
100
-
kHz
Adjacent channel gain
13.21
GAC
Gain
Adjacent channel filter
13.22
fHP
13.23
f-20dB
Attenuation 20dB
-
-
70
-
kHz
13.24
fBP
Centre frequency
ACF=1
-
100
-
kHz
-
-
12
-
dB
Multipath channel gain
13.25
GMP
Gain
Multipath bandpass filter
13.26
fC
Centre frequency
-
-
19
-
kHz
13.27
Q
Quality factor
-
5
8
10
-
14. ISS (intelligent selectivity system) filter 450kHz
14.1
fcentre
Centre frequency
fREF_intern = 450kHz
14.2
BW 3dB
Bandwidth, -3 dB
ISSBW = 1
70
80
90
kHz
14.3
BW 20dB Bandwidth, -20 dB
ISSBW = 1
132
150
168
kHz
14.4
BW 3dB
ISSBW = 0
106
120
135
kHz
14.5
BW 20dB Bandwidth, -20 dB
ISSBW = 0
220
250
280
kHz
14.6
BW 3dB
WBON = 1
18
22
26
kHz
14.7
BW 20dB -20dB weather band
WBON = 1
-
70
-
kHz
Bandwidth, -3 dB
Bandwidth weather band
450
kHz
Adjacent channel ISS filter threshold
14.8
VTHAC
Internal low threshold
ACTH
-
2.75
-
V
14.9
VTHAC
Internal high threshold
ACTH
-
3.05
-
V
Multipath threshold
14.10
VTHMP
Internal low threshold
MPTH
-
0.50
-
V
14.11
VTHMP
Internal high threshold
MPTH
-
1.25
-
V
ISS filter time constant
14.12
I30,31
Charge current low mid
TISS, BWDEF = 1
-89
-74
-59
µA
14.13
I30,31
Charge current high mid
TISS, BWDEF = 1
-72
-60
-48
µA
14.14
I30,31
Charge current low narrow TISS, BWDEF = 1
-148
-124
-99
µA
14.15
I30,31
Charge current high
narrow
TISS, BWDEF = 1
-132
-110
-88
µA
14.16
I30,31
Discharge current low
TISS, BWDEF = 0
0.5
1
1.5
µA
Doc ID 16048 Rev 1
15/77
Electrical specifications and characteristics
Table 6.
TDA7541B
FM section (continued)
Item
Symbol
Parameter
Test conditions
Min.
Typ.
Max.
Unit
14.17
I30,31
Discharge current high
TISS, BWDEF = 0
11
15
19
µA
14.18
V30,31
Low voltage
BWDEF = 0
-
0.1
0.2
V
14.19
V30,31
High voltage
BWDEF = 1
4.6
4.9
-
V
ISS filter switch threshold
14.20
V30,31
Threshold ISS on
BWDEF = 0
-
3
-
V
14.21
V30,31
Threshold ISS off
BWDEF = 0
-
1
-
V
14.22
V30,31
Threshold ISS narrow on
BWDEF = 0
-
4
-
V
14.23
V30,31
Threshold ISS narrow off
BWDEF = 0
-
2
-
V
Deviation detection
14.24
I3
Charge current low
TDEV
-40
-32
-20
µA
14.25
I3
Charge current high
TDEV
-48
-39
-30
µA
14.26
I3
Discharge current low
TDEV
0.5
1
1.5
µA
14.27
I3
Discharge current high
TDEV
5.5
8
10.5
µA
14.28
DEVWTH Internal low threshold
DWTH, I3 = 1 µA
-
20
-
kHz
14.29
DEVWTH Internal high threshold
DWTH, I3 = 1 µA
-
50
-
kHz
14.30 RATIOmin Referred to threshold
DTH
-
1
-
14.31 RATIOmax Referred to threshold
DTH
-
1.5
-
15. Weak signal mute
15.1
V37
Upper start point
WMTH = 0, WMD = 7, VIN=V56,
AF = -3 dB
-
2.9
-
V
15.2
V37
Lower start point
WMTH = 7, WMD = 7, VIN=V56,
AF = -3 dB
-
2.7
-
V
15.3
aWMD
Min. mute depth
WMD = 0, WMTH = 7, V56 =OFF
10
14
-
dB
15.4
aWMD
Max. mute depth
WMD = 7, WMTH = 7, V56=OFF
22
26
-
dB
15.5
aMTHISS
Mute threshold below
WMTH for ISS filter “ON”
WMD, WMTH, VIN=V56
-
1
-
dB
15.6
VACMTH
Internal AC mute
threshold
ACMTH
40
-
260
mV
15.7
aACMD
AC mute depth
ACMD
3
-
8
dB
15.8
I42
Charge current
-
-65
-47.5
-30
μA
15.9
I42
Discharge current
-
1.5
2.5
4
μA
16. Multiplexer output
16.1
V23
Output voltage low
-
-
0.1
0.2
V
16.2
V23
Output voltage high
-
4.6
4.9
-
V
16.3
ROUT
Output resistance
-
200
250
300
Ω
16.4
R23load
Load resistor
-
20
-
-
kΩ
16/77
Doc ID 16048 Rev 1
TDA7541B
3.3.3
Electrical specifications and characteristics
AM section
Tamb = 25 °C, VCC1 = VCC2 = VCCMIX1 = VCCVCO = VCCIF = 8.5 V, fXtal = 10.25 MHz,
fRF = 1 MHz, m = 30%, fmod = 1 kHz, in application circuit, unless otherwise specified.
Table 7.
Item
AM section
Symbol
Parameter
Test conditions
Min.
Typ. Max.
Unit
17. Global
17.1
VANT_US
Usable sensitivity (1)
(S+N)/N = 26 dB
17.2
(S+N)/N
Signal to Noise Ratio
17.3
aIF
IF1 rejection
17.4
V3
Min. RF AGC threshold
17.5
V3
Max. RF AGC threshold
17.6
V61
Min. IF AGC threshold
17.7
V61
Max. IF AGC threshold
17.8
V56
Min. DAGC threshold
V56
Max. DAGC threshold
17.9
-
19
25
dBµV
Ref.: V3 = 80 dBµV
50
55
-
dB
S/N = 26 dB, m = 30 %, fmod = 1 kHz
70
80
-
dB
-
92
-
dBµV
-
104
-
dBµV
-
78
-
dBµV
-
102
-
dBµV
-
86
-
dBµV
-
98
-
dBµV
RFAGC
IFAGC
DAGC
18. AGC voltage driver output
18.1
V4
Max. AGC output voltage
-
3.3
3.5
-
V
18.2
V4
Min. AGC output voltage
-
-
-
0.5
V
18.3
| I4 |
AGC current
V4 = 0 V, V54 = 3.5 V, LNA”00”
-
340
-
µA
-
-
-
-15
mA
19. AGC PIN diode driver output
19.1
I7
AGC driver current
20. AM Mixer1 (10.7 MHz)
20.1
RIN
Input resistance
differential
45
-
-
kΩ
20.2
CIN
Input capacitance
differential
-
2.5
-
pF
20.3
ROUT
Output impedance
-
530
660
790
Ω
20.4
CP1dB
1dB compression point
referred to diff. mixer input
-
112
-
dBμV
20.5
V3,6
Input DC bias
-
0.3
0.4
0.55
V
20.6
IIP3
3rd
-
-
132
-
dBμV
20.7
INOISE
Equivalent input noise
-
-
5.5
-
nV/√Hz
20.8
G
Gain
With 330 Ω filter
3
5.5
7
dB
order intermodulation
21. AM mixer2
21.1
RIN
Input resistance
-
240
300
360
Ω
21.2
CIN
Input capacitance
-
-
2.5
-
pF
21.3
V55.56
DC input voltage
-
3.8
4
4.2
V
21.4
ROUT
Output resistance
-
100
-
-
kΩ
Doc ID 16048 Rev 1
17/77
Electrical specifications and characteristics
Table 7.
TDA7541B
AM section (continued)
Item
Symbol
21.5
COUT
Output capacitance
-
-
2.5
-
pF
21.6
V52,53
DC output voltage
-
3.7
4.0
4.3
V
21.7
gm
Conversion
transconductance
MIX2OUT
-
440
-
µA/V
21.8
Gmax
Max. gain
L = 560 µH, Q = 28; C = 180 pF,
referred to MIX2OUT
-
26
-
dB
21.9
ΔG
Gain control range
-
-
20
-
dB
21.10
Cstep
Min. cap. Step
IF2A
-
2.2
-
pF
21.11
Cmax
Max. cap.
IF2A
-
33
-
pF
21.12
INOISE
Equivalent input noise
voltage,
including buffer mixer2
Amax, Rgen= 330 Ω, RL = 2 kΩ, noise
of Rgen not included
-
11
-
nV/√H
z
21.13
CP1dB
1dB compression point
Amax, referred to 330 Ω input
-
114
-
dBμV
Amax, referred to 330 Ω input
-
132
-
dBμV
21.14
IIP3
Parameter
rd
3 order Intermodulation
Test conditions
Min.
Typ. Max.
Unit
22. Buffer AM mixer2
22.1
ROUT
Output resistance
-
1.6
2
2.4
kΩ
22.2
COUT
Output capacitance
-
-
2.5
-
pF
22.3
V50
DC output voltage
-
3.7
4.0
4.3
V
22.4
G
gain
RL = 2 kΩ
-8
-6
-4
dB
23. AM IF2 amplifier
23.1
RIN
Input resistance
-
1.6
2
2.4
kΩ
23.2
CIN
Input capacitance
-
-
2.5
-
pF
23.3
V44,47
DC input voltage
-
4.1
4.3
4.5
V
23.4
Gmax
Max. gain
-
49
52
55
dB
23.5
ΔG
Gain control range
-
36
38
40
dB
23.6
INOISE
Equivalent input noise
voltage
Gmax, Rgen = 2 kΩ,
noise of Rgen not included
-
9.5
-
nV/√Hz
23.7
CP1dB
1 dB compression point
Gmax, referred to 2 kΩ input
-
74
-
dBμV
-
100
-
dBμV
140
190
240
mVRMS
-
62
-
dBµV
50
55
-
dB
-
50
-
µA/V
rd
23.8
IIP3
3 order Intermodulation
Gmax, referred to 2 kΩ input
23.9
V23
IF2 output voltage
V56 = 90 dBV, m = off
24. AMAGC2
24.1
VAGC(start) AGC start voltage (PIN47)
Input carrier voltage
24.2
ΔAGC
AGC2 range
Between start of AGC2
and the intervention point
of prestage AGC
24.3
gAGC
Control slope
Seek mode
18/77
Doc ID 16048 Rev 1
TDA7541B
Table 7.
Electrical specifications and characteristics
AM section (continued)
Item
Symbol
Parameter
Test conditions
Min.
Typ. Max.
Unit
24.4
gAGC
Control slope
normal mode
-
5
-
µA/V
24.5
II57I
Max. AGC charge current
Seek mode
-
125
-
μA
24.6
II57I
Max. AGC charge current
normal mode
-
5
-
μA
24.7
V57
Max. AGC output voltage
V47 = 100 dBµ
4.6
4.8
-
V
24.8
V57
Min. AGC output voltage
V47 = 20 dBµ
-
0.2
0.5
V
V56 = 90 dBµ, m = 30 %,
fmod = 1KHz
170
200
230
mVRM
V56 = 90 dBµ, m = 30 %,
fmod = 1 kHz
-
0.3
0.5
V56 = 90 dBµ, m = 80%,
fmod = 1 kHz
-
0.5
0.9
-
20
25
30
Ω
25. AM audio output
25.1
V43
Audio output voltage
25.2
THD
Total harmonic distortion
25.3
25.4
ROUT
Output impedance
S
%
26. IF noise blanking
26.1
tbl
Min. blanking time
-
-
8
-
μs
26.2
tbl
Max. blanking time
-
-
17
-
μs
26.3
Vth
Min internal threshold
-
-
50
-
mV
26.4
Vth
Max. internal threshold
-
-
187.5
-
mV
26.5
Vthstep
Threshold step
-
-
12.5
-
mV
1. Can be reached in application circuit, not measured.
3.3.4
Stereo decoder section
Tamb = 25 °C, VCC1 = VCC2 = VCCMIX1 = VCCVCO = VCCIF = 8.5 V, fXtal = 10.25 MHz,
VMPX = 500 mVrms mono, f = 1 kHz, de-emphasis τ = 50 µs, in application circuit, unless
otherwise specified.
Table 8.
Item
Stereo decoder section
Symbol
Parameter
Test conditions
Min.
Typ.
Max.
-
-
0.5
0.93
WBON = 1
-
0.05
0.06
Unit
27. Stereo decoder
27.1
Vin
MPX input level
27.3
Rin
Input resistance
-
80
100
120
kΩ
27.4
GSTD
Stereo decoder gain
-
2
2.5
3
dB
27.5
GSTDWB
Stereo decoder gain
Weather band mode
23
26
27
dB
27.6
SVRR
Supply voltage ripple
rejection
Vripple = 100 mV, f = 1 kHz
-
60
-
dB
27.2
Doc ID 16048 Rev 1
Vrms
19/77
Electrical specifications and characteristics
Table 8.
TDA7541B
Stereo decoder section (continued)
Item
Symbol
27.7
A
27.8
27.9
Parameter
Test conditions
Min.
Typ.
Max.
Unit
35
40
-
dB
channel separation
VMPX = 500 mVrms stereo, only
L/R, ROC adjusted
THD
Total harmonic distortion
-
-
0.02
0.3
%
(S+N)/N
Signal plus noise to noise
ratio
A-weighted, 19 kHz notch
-
85
-
dB
28. Mono/stereo switch
28.1
VPTHST1
Pilot threshold voltage
for Stereo, PTH = 1
5
8
12
mVrms
28.2
VPTHST0
Pilot threshold voltage
for Stereo, PTH = 0
7
11
16
mVrms
28.3
VPTHMO1 Pilot threshold voltage
for Mono, PTH = 1
3.5
6
10
mVrms
28.4
VPTHMO0 Pilot threshold voltage
for Mono, PTH = 0
6
9
14
mVrms
18.9
-
19.1
kHz
29. 19kHz PLL
29.1
flock
Capture range
Pilot magnitude 20 mVrms = 4 %
29.2
DP
Pilot deviation range
fpilot = 19 kHz
4
-
30
%
30. De-emphasis and high cut
30.1
tHC50
De-emphasis time
constant
DEEMP=0, High Cut OFF
45
50
55
μs
30.2
tHC75
De-emphasis time
constant
DEEMP = 1, High Cut OFF
67
75
83
μs
30.3
tHC50
High cut time constant
DEEMP = 0, High Cut ON,
V28=0.1V
135
150
165
μs
30.4
tHC75
High cut time constant
DEEMP= 1, High Cut ON,
V28 = 0.1 V
200
225
250
μs
30.5
AAmmin
Min. Attenuation in AM
Voutmax/Vout@ f = 3.5 kHz,
DEEMP = 0, AMCF “111”
-
3.6
-
dB
30.6
AAmmax
Max. Attenuation in AM
Voutmax/Vout@ f = 3.5 kHz,
DEEMP= 0, AMCF “000”
-
8
-
dB
31. Stereo blend and high cut control
31.1
LGmin
Min. level gain
LG
-0.3
0
0.3
dB
31.2
LGmax
Max. level gain
LG
7.75
8.25
8.75
dB
31.3
LGstep
Level gain step Resolution -
0.25
0.55
0.85
dB
31.4
VSBLmin Min. voltage for mono
SBC
24
29
34
%VREF1
31.5
VSBLmax Max. voltage for mono
SBC
53
58
63
%VREF1
31.6
VSBLstep Step resolution
SBC
3.5
4.2
5
%VREF1
31.7
VHCHmin
Min. voltage for no high
cut
HCHT
37
42
47
%VREF1
31.8
VHCHmax
Max.voltage for no high
cut
HCHT
61
66
71
%VREF1
20/77
Doc ID 16048 Rev 1
TDA7541B
Table 8.
Item
Electrical specifications and characteristics
Stereo decoder section (continued)
Min.
Typ.
Max.
Unit
HCHT
7
8
9
%VREF1
31.10 VHCLmin Min. voltage for full high cut HCLT
6
11
16
%VHCH
31.11 VHCLmax Max. voltage for full high cut HCLT
28
33
38
%VHCH
31.12 VHCLstep Step resolution
6.5
7.3
8.1
%VHCH
31.9
Symbol
Parameter
VHCHstep Step resolution
Test conditions
HCLT
32. Carrier and harmonic suppression at the output
32.1
a19
Pilot signal f = 19 kHz
-
45
50
-
dB
32.2
a38
Subcarrier f = 38 kHz
-
-
75
-
dB
32.3
a57
Subcarrier f = 57 kHz
-
-
62
-
dB
32.4
a76
Subcarrier f = 76 kHz
-
-
90
-
dB
33. Intermodulation (1)
33.1
a2
fmod = 10 kHz, fspur =1 kHz -
-
65
-
dB
33.2
a3
fmod = 13 kHz, fspur =1 kHz -
-
75
-
dB
34. Traffic radio (2)
34.1
a57
35. SCA
35.1
Signal f = 57 kHz
-
65
70
-
dB
Signal f = 67 kHz
-
-
75
-
dB
(3)
a67
36. ACI – adjacent channel interference (4)
36.1
a114
Signal f = 114 kHz
-
-
95
-
dB
36.2
a190
Signal f = 190 kHz
-
-
84
-
dB
37. FM noise blanker
37.1
VTRMIN
Min. trigger threshold (5)
VPEAK=0.8 V, NBLT “111”
-
147
-
mVOP
37.2
VTRMAX
Max. trigger threshold (5)
VPEAK=0.8 V, NBLT “000”
-
280
-
mVOP
37.3
VTRNOISE
Min. noise controlled
trigger threshold
VPEAK = 1.5 V, NBCT “11”
-
450
-
mVOP
37.4
VTRNOISE
Max. noise controlled
trigger threshold
VPEAK = 1.5 V, NBCT “00”
-
1200
-
mVOP
37.5
VPEAK
Peak voltage
NBRR “00”, VMPX = 0 mV
-
0.8
-
V
37.6
VPEAK
Peak voltage
NBRR “00”, VMPX = 50 mV,
f = 150 kHz
-
1.9
-
V
37.7
VPEAK
Peak voltage
NBRR “00”, VMPX = 200 mV,
f = 150 kHz
-
3.5
-
V
37.8
VPEAKDEV
Min. deviation dependent
peak voltage
VMPX = 500 mV,
NBDC = 11 (“OFF”)
-
0.8
-
V
37.9
VPEAKDEV
Max. deviation dependent
VMPX = 500 mV, NBDC= 00
peak voltage
-
2.0
-
V
Doc ID 16048 Rev 1
21/77
Electrical specifications and characteristics
Table 8.
TDA7541B
Stereo decoder section (continued)
Item
Symbol
Parameter
37.10
VPEAKFS
Min. fieldstrength
controlled peak voltage
37.11
VPEAKFS
37.12
Test conditions
Min.
Typ.
Max.
Unit
VMPX=0mV, VLEVEL<< VSBL
(fully mono), NBFC = 11 (“OFF”)
-
0.8
-
V
Max. fieldstrength
controlled peak voltage
VMPX=0mV, VLEVEL<< VSBL
(fully mono), NBFC = 00
-
2.0
-
V
TS
Min. blanking time
Signal HOLDN in testmode,
NBT = 00
-
38
-
μs
37.13
TS
Max. blanking time
Signal HOLDN in testmode,
NBT = 11
-
22
-
μs
37.14
SRPEAK
Noise rectifier charge
Signal PEAK in testmode,
NBPC =0
-
5
-
mV/μs
37.15
SRPEAK
Noise rectifier charge
Signal PEAK in testmode,
NBPC=1
-
12
-
mV/μs
37.16 VRECTADJ
Noise rectifier discharge
adjustment
Signal PEAK in testmode,
NBRR=00
-
0.3
-
V/ms
37.17 VRECTADJ
Noise rectifier discharge
adjustment
Signal PEAK in testmode,
NBRR=01
-
1.8
-
V/ms
37.18 VRECTADJ
Noise rectifier discharge
adjustment
Signal PEAK in testmode,
NBRR=10
-
2.8
-
V/ms
37.19 VRECTADJ
Noise rectifier discharge
adjustment
Signal PEAK in testmode,
NBRR=11
-
4
-
V/ms
37.20
VADJMP
Noise rectifier adjustment
by multipath
Signal PEAK in testmode,
VMPTC=1V, NBSMP=0, NBMP=1,
NBRR=01
-
3
-
V/ms
37.21
VADJMP
Noise rectifier adjustment
by strong multipath
influence
Signal PEAK in testmode,
VMPTC = 1V, NBSMP = 1,
NBMP = 0, NBRR = 01
-
4
-
V/ms
37.22
VADJMP
Noise rectifier adjustment
by multipath and strong
multipath influence
Signal PEAK in testmode,
VMPTC=1 V, MBSMP=1,
NBMP=1, NBRR=01
-
5.2
-
V/ms
38. Multipath detector
38.1
GMP
Min. multipath gain
MPG = 00
5
6
7
dB
38.2
GMP
Max. multipath gain
MPG = 11
11
12
13
dB
38.3
GRECTMP Min. rectifier gain
MPRG = 01
-1
0
1
dB
38.4
GRECTMP Max. rectifier gain
MPRG = 11
5
7.6
9
dB
38.5
ICHMP
Rectifier charge current
MPCC = 0
0.5
0.8
1.1
μA
38.6
ICHMP
Rectifier charge current
MPCC = 1
0.2
0.4
0.7
μA
38.7
IDISMP
Rectifier discharge current
0.5
1
-
mA
0.5
0.6
0.7
-
39. Quality detector
39.1
22/77
a
Min. quality detector
coefficient
QDC
Doc ID 16048 Rev 1
TDA7541B
Table 8.
Electrical specifications and characteristics
Stereo decoder section (continued)
Item
Symbol
Parameter
39.2
a
Max. quality detector
coefficient
39.3
b
39.4
b
Test conditions
Min.
Typ.
Max.
Unit
QDC
0.9
1.05
1.2
-
Min. quality noise gain
QNG
5
6
7
dB
Max. quality noise gain
QNG
13
15
17
dB
1. Intermodulation suppression
V o ( signal ,@1 kHz )
a2 = --------------------------------------------------------------- ;ƒs = ( ( 2 × 10 kHz ) – 19 kHz )
V o ( spurious ,@1 kHz )
V o ( signal ,@1 kHz )
a3 = --------------------------------------------------------------- ;ƒs = ( ( 3 × 13 kHz ) – 38 kHz )
V o ( spurious ,@1 kHz )
measured with: 91 % stereo signal; 9 % pilot signal; fm = 10 kHz or 13 kHz.
2. Traffic radio (V.F.) suppression
V o ( signal ,@1 kHz )
a57 ( V ,W ,F ) = ----------------------------------------------------------------------------------------V o ( spurious ,@1 kHz ) ± 23 kHz
measured with: 91% stereo signal; 9% pilot signal; fm=1 kHz; 5% sub carrier (f=57 kHz, fm=23 Hz AM, m=60 %)
3. SCA (subsidiary communications authorization)
V o ( signal ,@1 kHz )
a67 = --------------------------------------------------------------- ;ƒs = ( ( 2 × 38 kHz ) – 67 kHz )
V o ( spurious ,@9 kHz )
measured with: 81 % mono signal; 9 % pilot signal; fm=1 kHz; 10 % SCA - sub carrier (fS = 67 kHz, unmodulated)
4. ACI (adjacent channel interference)
V o ( signal ,@1 kHz )
a114 = --------------------------------------------------------------- ;ƒs = ( 110 kHz – ( 2 × 38 kHz ) )
V o ( spurious ,@4 kHz )
V o ( signal ,@1 kHz )
a190 = --------------------------------------------------------------- ; ƒs = ( 186 kHz – ( 5 × 38 kHz ) )
V o ( spurious ,@4 kHz )
measured with: 90 % mono signal; 9 % pilot signal; fm=1 kHz; 1% spurious signal (fS = 110 kHz or 186 kHz, unmodulated)
5. All thresholds are measured in test mode at the quality output. The thresholds are calculated by VNBTH - VPEAK. VPEAK can
be adjusted by applying a 150 kHz sinewave at MPXIN.
Doc ID 16048 Rev 1
23/77
Electrical specifications and characteristics
3.3.5
TDA7541B
PLL section
Tamb = 25 °C, VCC1 = VCC2 = VCCMIX1 = VCCVCO = VCCIF = 8.5 V, fXtal = 10.25 MHz,
VMPX = 500 mVrms mono, f = 1 kHz, de-emphasis τ = 50 µs, in application circuit, unless
otherwise specified.
Table 9.
PLL section
Item Symbol
Parameter
Test conditions
Min.
Typ.
Max.
Unit
40. Voltage controlled oscillator (VCO)
40.1
fVCOmin
Min. VCO frequency
-
160
-
-
MHz
40.2
fVCOmax Max. VCO frequency
-
-
-
260
MHz
fVCO= 200 MHz, Δf=1 kHz,
B = 1 Hz, Qloaded=60
-
80
-
dBc/√Hz
-
10.25
-
MHz
110
-
-
dBc/√Hz
40.3
C/N
Carrier-to-noise-ratio
41. Crystal oscillator
41.1
fxtal
Crystal frequency
-
41.2
C/N
Carrier-to-noise-ratio
fxtal =10.25 MHz, Δf=10 kHz
41.3
V29
Oscillator output voltage
-
-
400
-
mVrms
41.4
C29-32
Input capacitance
-
-
2.5
-
pF
41.5
Cstep
Min. cap. Step
XTAL
-
0.75
-
pF
41.6
Cmax
Max. cap.
XTAL
-
23.25
-
pF
41.7
Δf/f
Deviation versus VCC
Δ VCC=1 V
-
1.5
-
ppm/V
41.8
Δf/f
Deviation versus T
-40 °C<T<+85 °C
-
0.2
-
ppm/K
-
50
-
μA
-
50
-
μA
-
550
-
μA
-
500
-
μA
-
1
-
mA
-
1
-
mA
-
1.9
-
mA
-
1.9
-
mA
42. Charge pump current
42.1
-I20
Source current
42.2
I20
Sink current
42.3
-I20
Source current
42.4
I20
Sink current
42.5
-I20
Source current
42.6
I20
Sink current
42.7
-I20
Source current
42.8
I20
Sink current
V20 = 2.5 V
ICP, V20 = 2.5 V
ICP, V20 = 2.5 V
43. Loop filter input/output
43.1
-IIN
Input leakage current
VIN = GND: PDOUT = Tristate
-0.1
-
0.1
μA
43.2
IIN
Input leakage current
VIN = VREF1 PDOUT = Tristate
-0.1
-
0.1
μA
43.3
VOL
Output voltage Low
IOUT = -0.2 mA
-
0.05
0.5
V
43.4
VOH
Output voltage High
IOUT = 0.2 mA
-
V
43.5
IOUT
Output current, sink
VOUT = 1 V to VCCVCO-1 V
-
-
10
mA
43.6
IOUT
Output current, source
VOUT = 1 V to VCCVCO-1 V
-10
-
-
mA
24/77
Doc ID 16048 Rev 1
VCCVCO- VCCVCO0.5
0.05
TDA7541B
Table 9.
Electrical specifications and characteristics
PLL section (continued)
Item Symbol
Parameter
Test conditions
Min.
Typ.
Max.
Unit
0.5
-
VVCO0.5
V
44. Output of tuning voltage (TV)
44.1
VOUT
Output voltage
-
44.2
IVstepI
Min. voltage step
TVO
-
25
-
mV
44.3
IVmaxI
Max. voltage offset
TVO
-
3175
-
mV
44.4
ΔV
Additional offset voltage
TVM=1, TVO+
-
3.175
-
V
44.5
ROUT
Output impedance
TVM=0
-
40
-
kΩ
44.6
ROUT
Output impedance
TVM=1
-
20
-
kΩ
45. SSTOP output (open collector)
45.1
V24
Output voltage low
I24 = -200 μA
-
0.2
0.5
V
45.2
V24
Output voltage high
-
-
-
5
V
45.3
-I24
Output leakage current
V 24 = 5 V
-0.1
-
0.1
μA
45.4
I24
Output current, sink
V 24 = 0.5 V to 5 V
-
1
mA
45.5
Internal unfiltered field
V37SSTH strength threshold for
SSTOP=HIGH
SSTH, FMON=1
2.6
-
4.1
V
45.6
Internal unfiltered field
V27SSTH strength threshold for
SSTOP=HIGH
SSTH, FMON=0
SL = “011”
1.2
-
4.8
V
46. Switch output
46.1
VOL
Output Voltage low
SWM”1”,SW”0”, I24 = -5 µA
-
0.35
0.5
V
46.2
VOH
Output Voltage high
SWM”1”,SW”1”
-
VCC-1
-
V
46.3
-I22
Output leakage current
V22=5 V
-0.5
-
0.5
μA
46.4
I22
Output Current, sink
-
-
-
7
mA
46.5
VOL
Output Voltage low
SWM”0”,SW”0”, I22=0 µA
-
0.1
0.3
V
46.6
VOH
Output Voltage high
SWM”0”,SW”1”, I22=1 mA
-
VCC-1
-
V
46.7
I22
Output Current, sink
V22=5 V
-7
-
-
mA
Doc ID 16048 Rev 1
25/77
Functional description
TDA7541B
4
Functional description
4.1
FM part
4.1.1
Mixer 1 AGC and IF amplifier
FM quadrate I/Q-mixer converts FM RF to IF1 of 10.7 MHz. The mixer provides inherent
image rejection and wide dynamic range with low noise and large input signal performance.
For accurate image rejection the phase-error of I/Q can be compensated by software (PH).
It is capable of tuning the US FM, US weather (dedicated WB input), Europe FM, Japan FM
and East Europe FM bands:
–
US FM = 87.9 to 107.9 MHz
–
US weather = 162.4 to 162.55 MHz
–
Europe FM = 87.5 to 108 MHz
–
Japan FM = 76 to 91 MHz
–
East Europe FM = 65.8 to 74 MHz
The AGC operates on different sensitivities and bandwidths in order to improve the input
sensitivity and dynamic range. AGC thresholds are programmable by software (RFAGC,
IFAGC, and KAGC). The output signal is a controlled current for pin diode attenuator.
A 10.7 MHz programmable amplifier (IFG) correct the IF ceramic insertion loss and the
costumer level plan application.
4.1.2
Mixer2, limiter, FM demodulator and spike cancellation
In the 2nd mixer stage the first 10.7 MHz IF is converted into the second 450 kHz IF.
The fully integrated sample and hold FM demodulator including spike cancellation (DSB)
converts the IF signal from the 450 kHz limiter (limiter gain 80 dB typ.) to the FM multiplex
output signal with very low distortion.
The sensitivity of spike blanking can be set via I2C bus.
4.1.3
Quality detection and ISS
Field strength
Parallel to mixer2 input a 10.7 MHz limiter generates a signal for digital IF counter and field
strength voltage VFSUint. This internal voltage VFSUint is used for AM IF noise blanker,
adjacent channel and multi path detection and is available at PIN27 (FSU) in a range of 0 V
to 5 V. The offset and slope of FSU signal can be adjusted via I2C bus (FSWO and SL) for
application adaptation.
The voltage VFSWO including offset adjust is externally filtered at PIN37 (FSWO) and used
for weak signal mute function and generation of ISS filter control signals in weak signal
condition. It is possible to combine the IF counter result with this voltage VFSWO by
programmable comparator threshold (SSTH).
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Functional description
Adjacent channel detector
The input of the adjacent channel detector is AC coupled from VFSW. A programmable
high-pass or band-pass (ACF) as well as rectifier generate a signal which is compared with
adjustable threshold (ACTH). The output signals of this comparator is controlling the charge
and discharge of the external capacitor at PIN30 or PIN31 (dependent on SEEK) with
programmable discharge current (TISS). The level at PIN30/31 is used to generate the two
digital signal ac and ac+ for ISS control. The adjacent channel information behind the
rectifier is available as analog output signal at the multiplexer output (PIN23).
Multipath detector
The input of the multi path detector is AC coupled from internal VFSW too. After filtering with
19 kHz band-pass and rectifying, this voltage is compared with an adjustable threshold
(MPTH). The output signal of this comparator can be used to switch off the adjacent channel
detection. This influence is selectable by I2C bus (MPENA).
The multi path information behind the rectifier is available as analog output signal at
multiplexer output (PIN23).
450 kHz IF narrow band pass filter (ISS filter)
The device has an additional 450 kHz IF narrow band-pass filter for suppression of noise
and adjacent channel signal influences. This narrow filter has three switchable bandwidths,
narrow range of 80 kHz, mid range of 120 kHz and 22 kHz for weather band information.
Without ISS (Intelligent Selectivity System) filter the IF bandwidth (wide range) is defined
only by ceramic filter chain and mixer2 bandwidth. The filter is located between mixer2
output buffer and 450 kHz limiter stage. The centre frequency is matched to the
demodulator centre frequency.
Deviation detector
In order to avoid distortion in audio output signal the narrow ISS filter is switched OFF if over
deviation is present. Hence the demodulator output signal is detected. After AC coupling,
low-pass filtering and peak rectifying this signal is charging/discharging the external DEVTC
capacitor by an IIC programmable charge/discharge current (TDEV). The voltage at DEVTC
is compared with adjustable thresholds (DWTH, DTH) and generates two digital control
signals (dev, dev+). For weak signal condition the deviation threshold depends on FSWO.
ISS switch logic
All digital control signals coming from adjacent channel detector, deviation detector and
weak signal mute are acting via switching matrix on ISS filter switch. IF2 narrow band-pass
switch mode is controlled also by software (ISSENA, ISSON, WBON, ISSBW, and BWDEF).
The switching of the IF band-pass is also possible to influence by external manipulation of
DC voltage at PIN30.
The influence of the ISS software control on the functionality of the ISS filter is described in
Table 10. The value “X” for the control bit means the bit does not influence the filter control in
this condition.
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Functional description
TDA7541B
ISS filter control by I2C bus
Table 10.
ISSENA adr4/d2
ISSON adr11/d0
ISSBW adr7/d0
WBON adr11/d1
ISSM adr9/d7
BWDEF adr7/d1
I2C control bits
0
X
X
X
X
X
ISS filter is switched off (bypass)
1
1
0
X
X
X
ISS filter is in manual control mode, Band width is 120 kHz
1
1
1
X
X
X
ISS filter is in manual control mode, Band width is 80 kHz
1
1
X
1
X
X
ISS filter is in manual control mode, Band width is 22 kHz
This setting must be used for weather band application
1
0
X
X
0
0
ISS filter is in automatic control mode
Filter activation and band width defined by control table mode1
1
0
X
X
1
0
ISS filter is in automatic control mode
Filter activation and band width defined by control table mode2
1
0
0
X
0
1
ISS filter is in automatic control mode
Filter activation defined by control table mode1
band width fixed to 120 kHz
1
0
0
X
1
1
ISS filter is in automatic control mode
Filter activation defined by control table mode2
band width fixed to 120 kHz
1
0
1
X
0
1
ISS filter is in automatic control mode
Filter activation defined by control table mode1
band width fixed to 80 kHz
1
0
1
X
1
1
ISS filter is in automatic control mode
Filter activation defined by control table mode2
band width fixed to 80 kHz
Notes
Description of I2C bits:
ISSENA
ISS filter enable
“1”: ISS filter control enabled
“0”: ISS filter is switched off (bypass of the filter, wide)
ISSON
ISS filter control mode
“1”: ISS filter is in manual control mode (switched "ON"); the bits ISSBW and WBON are
defining the bandwidth
“0”: ISS filter is in automatic control mode according to mode1/2 table
ISSBW
ISS filter band width
“1”: 80 kHz
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Functional description
“0”: 120 kHz
The bit has only influence if bit BWENA is “1”, or if bit ISSON is “1”
WBON
Weather band enable
“1”: Weather band enable (FMmixer1 is disabled, Wbmixer1enabled, stereo decoder gain
26dB, ISS filter bandwidth 22 kHz, IF2Q=”00”)
“0”: Weather band disable
For weather band enable it is need to set ISSON = “1”
ISSM
ISS filter application mode
“0”: ISS filter application mode1
“1”: ISS filter application mode2
If BWENA is “1” the band width is always switched to ISSBW in case of ISS filter activated
BWDEF
Enable bit ISSBW for ISS filter band with control
“1”: ISS filter is internally controlled, but band width is defined by bit ISSBW
“0”: ISS filter is internally controlled, band width is defined by mode1/2 table
For the internal control two application modes are available (ISSM). The conditions and
settings are described in Table 11 and Table 12.
4.1.4
Block diagram quality detection principle
(without overdeviation correction)
Table 11.
Signal
Internal ISS control signals
Low
High
Ac
No adjacent channel
Adjacent channel present
ac+
No strong adjacent channel
Adjacent channel higher as ac
Sm
Field strength higher as weak signal mute
threshold
Field strength lower as weak signal mute
threshold
Dev
Deviation lower as threshold DWTH
Deviation higher as threshold DWTH
dev+
Deviation lower as threshold DTH*DWTH
Deviation higher as threshold DTH*DWTH
Inton
ISS filter off by logic (wide)
ISS filter on by logic
int80
ISS filter 120 kHz (mid)
ISS filter 80 kHz (narrow)
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Functional description
Table 12.
TDA7541B
ISS control modes
Input signals
4.1.5
Mode1
Mode2
ac
ac+
sm
dev
dev+
inton
int80
Function
inton
int80
Function
0
0
0
0
0
0
0
wide
0
0
wide
0
0
0
1
0
0
0
wide
0
0
wide
0
0
0
1
1
0
0
wide
0
0
wide
0
0
1
0
0
1
1
narrow
1
1
narrow
0
0
1
1
0
0
0
wide
1
0
mid
0
0
1
1
1
0
0
wide
0
0
wide
1
0
0
0
0
1
1
narrow
1
0
mid
1
1
0
0
0
1
1
narrow
1
1
narrow
1
0
0
1
0
1
0
mid
1
0
mid
1
1
0
1
1
1
0
mid
1
1
narrow
Strong adjacent channel correction
Under strong adjacent channel it is possible to have disturbance of the audio signal created
by interference between ISS filter control (deviation detection) and adjacent channel mute.
The control bits SACCE and SACCT can be used to avoid this disturbance. If the function is
activated (SACCE = “1”) the IF counter together with the internal field strength is used to
suppress a malfunction of deviation detection. The bit SACCT is changing the sensitivity of
the SACC block (SACCT = “1” means higher sensitivity).
Figure 10 shows the ISS block diagram including the SACC function.
Note:
The IF counter must be switched ON if this function is used (Addr25D4 = “1”)
4.1.6
Weak signal mute
The filtered field strength signal (FSWO) is the reference for soft slope mute control in weak
signal condition to eliminate audible effects. The start point and mute depth are
programmable (WMTH, WMD) in a wide range. These settings together with FSWO bits are
influencing the weak signal mute behavior. The time constant is defined by external
capacitance at PIN 42. Additional adjacent channel mute function is supported. A high pass
filter with -3 dB threshold frequency of 100 kHz, amplifier and peak rectifier generates an
adjacent noise signal from Demodulator output. This value is compared with adjustable
threshold (ACMTH). For present strong adjacent channel the MPX signal is additional
attenuated (ACMD) and has the same time constant as weak signal mute.
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4.1.7
Functional description
Weather band input
If the weather band input is used the chip must be set in FM mode (FMON). In addition to
that the ISS filter must be switched ON (ISSENA=”1”), mixer2 quality factor must be set to
IF2Q=”00” and the ISS filter must be set in manual control mode (ISSON=”1”).
The bit WBON is:
●
activating the WB input
●
switching the ISS filter in WB mode (22 kHz band width)
●
switching the stereo decoder InGain to 26 dB.
In order to increase the selectivity in weather band mode the AM 450kHz ceramic filter can
be used in series to the ISS filter by activating ADSEL (please refer to Figure 10, ISS block
diagram and Section 4.2.1, usage of bit ADSEL).
4.2
AM section
signals, narrow band information (DAGC) referred to PIN 56, up conversion signal (IFAGC)
at PIN 61 and wide band information (RFAGC) at PIN 3.This gain control gives two output
signals. The first one is a current for pin diode attenuator and the second one is a voltage for
preamplifier. Time constant of RF and IF-AGC is defined by internal 100 kΩ resistor and
external capacitor at PIN 54. The intervention points for AGC (DAGC, IFAGC and RFAGC)
are programmable by software. The oscillator frequency for upconversion-mixer1 is
generated by dividing the VCO frequency after VCO divider (VCOD) and AM pre-divider
(AMD).
Two 10.7 MHz ceramic filters before mixer2 input increase 900 kHz attenuation.
The AMIF2 block contains mixer2, IF2 amplifier, demodulator and AGC2 The AM/FM mixer2
converts 10.7 MHz IF1 into 450 kHz IF2. Mixer2 output passes a 450 kHz narrow band filter
(LC plus ceramic filter). LC centre frequency is adjustable by I2C bus (IF2A). The following
IF2 amplifier provides signal for fully integrated demodulator. If the bit ADSEL is activated,
the ISS filter is inserted between IF2 amplifier and demodulator in order to increase the
selectivity (please refer to Figure 11, AM path block diagram and Section 4.2.1, usage of bit
ADSEL).
Mixer2 and IF2 amplifier have a 2-stage AGC with careful take-over behavior to keep
distortion low. The IF2 AGC range is about 55 dB.
The input signal of IF2 amplifier is used in limiter circuit for in-band level detection. The
electrical characteristics are described in FM section.
The demodulator is a peak detector to generate the audio output signal.
At the MUX output the AMIF stereo is available.
AM IF noise blanker
In order to remove in AM short spikes a noise cancellation conception is used in 450 kHz IF
AM level. The advantage is to avoid long narrow AGC- and demodulator- time constants,
which enlarge spike influences on audio signal and makes difficult to remove it in audio path.
The 10.7 MHz AM IF signal behind IF1 amplifier generates via limitation an unweighted field
strength signal including slope of noise spike. The comparison of this detected slope
between fast and slow rectifier ignores audio modulation whereby the threshold of slow
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Functional description
TDA7541B
rectifier is programmable (AINBT). A comparator activates a pulse generator. The duration
of this pulse is software programmable (AINT) and is smooth blanking out the spikes in mixer2.
4.2.1
Usage of control bit ADSEL (Addr23D7)
The control bit ADSEL can be used to increase the selectivity of the application in AM mode
and WB mode. In FM it has no function. Table 12 shows the functionality of the control bit.
Table 13.
FMON
Usage of ADSEL
WBON
ADSEL
Note
Addr4D7 Addr11D1 Addr23D7
1
0
X
Standard FM mode
1
1
0
Weather band mode using 450 kHz ceramic filter;
ISS filter must be manually switched on in order to limit the band
width at 450 kHz IF (ISSENA/ISSON = "1");
450 kHz ceramic filter is switched in series to ISS filter to
increase selectivity
1
1
1
Standard weather band mode;
ISS filter must be manually switched on in order to limit the band
width at 450 kHz IF (ISSENA/ISSON = "1")
0
0
0
Standard AM mode
0
0
1
AM mode using ISS filter;
ISS filter (22 kHz band width) is switched in series to the 450 kHz
ceramic filter
0
1
X
Not allowed
4.3
Stereo decoder
4.3.1
Decoder
The stereo decoder-part of the TDA7541B contains all functions necessary to demodulate
the MPX-signal, like pilot tone-dependent MONO/STEREO switching as well as the stereo
blend and high cut.
Adaptations like programmable input gain, roll-off compensation, selectable de-emphasis
time constant and a programmable field strength input allow easy adoption to different
applications.
The 4th order input filter has a corner frequency of 80 kHz and is used to attenuate spikes
and noise and acts as an anti-aliasing filter for the following switch capacitor filters.
Demodulator
In the demodulator block the left and the right channel are separated from the MPX-signal.
In this stage also the 19 kHz pilot tone is canceled. For reaching a high channel separation
the TDA7541B offers an I2C bus programmable roll-off adjustment, which is able to
compensate the low pass behavior of the tuner section. Within the compensation range an
adjustment to obtain about 40 dB channel separation is possible. The bits for this
adjustment are located together with the level gain adjustment in one byte. This gives the
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Functional description
possibility to perform an optimization step during the production of the car radio where the
channel separation and the field strength control are trimmed.
In addition to that the FM signal can be inverted.
De-emphasis and high cut
The de-emphasis low pass allows to choose between a time constant of 50 µs/75 µs
(DEEMP). The high cut control range will be in both cases THC = 2 x TDeemp. Inside the high
cut control range (between VHCHT and VHCLT) the LEVEL signal is converted into a 5-bit
word, which controls the low pass time constant between TDeemp...3 x TDeemp. Thereby the
resolution will remain 5 bits referred to the voltage range between the VHCHT- and minimum
VHCLT-values.
The high cut function can be switched off by I2C-bus.
Figure 3.
Programming of HC filter
High Cut Filter
Time Constant
00
3*TDeemp
11
HCMax
01
TDeemp
VFSTC* LG
VHCLT
VHCHT
In AM mode (FMON = 0) the DEEMP bit together with the AM corner frequency bits (AMCF)
can be used as programmable AM frequency response. The maximum corner frequency is
defined by TDeemp, the minimum is defined by 3 x TDeemp For the over all frequency
response it is need to take into account the frequency response of the AF output at
MPXOUT and the Stereo decoder demodulator too.
19 kHz PLL and pilot tone detector
The PLL has the task to lock on the 19 kHz pilot tone during a stereo-transmission to allow a
correct demodulation. The included pilot tone-detector enables the demodulation if the pilot
tone reaches the selected pilot tone threshold VPTHST. Two different thresholds are
available. The status of the detector output can be checked by reading the status byte of the
TDA7541B via I2C bus or by reading the STEREO status at MUX pin23.
Field strength control
The field strength input is used to control the high cut- and the stereo blend-function. In
addition the signal can be also used to control the noise blanker thresholds and as input for
the multipath detector.
Level input and gain
As level input for the stereo decoder is used the FSU voltage (pin 27). Applying a capacitor
at FSTC (pin28) a desired time constant can by reached together with the internal resistor of
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Functional description
TDA7541B
10k between FSU pin and FSTC pin. The second stage is a programmable gain stage to
adapt the VFSTC signal internally. The gain (LG) is widely programmable in 16 steps from
0 dB to 8.25 dB (step=0.55dB). These 4 bits are located together with the Roll-Off
compensation bits in byte 14 to simplify a possible adaptation during the production of the car radio.
Stereo blend control
The stereo blend control block converts the internal LEVEL-voltage into a demodulator
compatible analog signal, which is used to control the channel separation between 0dB and
the maximum separation. Internally this control range has a fixed upper limit, which is the
internal reference voltage VREF1. The lower limit can be programmed between 29 and
58 % of VREF1 in 4 % steps. In order to adjust the external voltage VFSTC to the internal
control range two values must be defined: the Level gain LG and VSBL. Full channel
separation is reached when the internal level voltage (VST) becomes bigger than VREF1.
Therefore the following equation can be used to estimate the gain:
V REF1
LG = ---------------------------------------------------V FSTC @ fullstereo
The MONO-voltage VMO (0dB channel separation) can be chosen selecting SBC.
Figure 4.
Programming of stereo blend
High cut control
The high cut control set-up is similar to the stereo blend control set-up: the starting point
VHCH can be set with 2 bits to be 42, 50, 58 or 66 % of VREF1 whereas the range can be
set to be 11, 18.3, 25.7 or 33 % of VHCH.
4.3.2
Noise blanker
In the automotive environment spikes produced for example by the ignition or the wipermotor disturb the MPX-signal. The aim of the noise blanker part is to cancel the audible
influence of the spikes. Therefore the output of the stereo decoder is held at the actual
voltage for a time between 22 ms and 38 ms (programmable).
In a first stage the spikes must be detected but to avoid a wrong triggering on high
frequency (white) noise a complex trigger control is implemented. Behind the trigger stage a
pulse former generates the "blanking"-pulse. An own biasing circuit supplies the noise
blanker in order to avoid any cross talk to the signal path.
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Functional description
Trigger path
The incoming FM demodulator output signal is taken in front of the weak signal mute, high
pass filtered, amplified and rectified. This second order high pass filter has a cornerfrequency of 140 kHz. The rectified signal, VRECT, is low pass filtered to generate a signal
called VPEAK. Noise with a frequency above 140 kHz increases the VPEAK voltage. The
resulting voltage can be adjusted by use of the noise rectifier discharge current. The VPEAK
voltage is fed to a threshold generator, which adds to the VPEAK voltage a DC threshold
VTH. Both signals, VRECT and VPEAK+VTH are fed to a comparator, which triggers a retriggerable monoflop. The output of the monoflop activates the sample-and-hold circuit in
the signal path for the selected duration.
Automatic noise controlled threshold adjustment
There are mainly two independent possibilities for programming the trigger threshold:
1.
Low threshold in 8 steps (NBLT)
2.
Noise adjusted threshold in 4 steps (NBCT).
The low threshold is active in combination with a good MPX signal without any noise; the
VPEAK voltage is less than 1V. The sensitivity in this operation is high.
If the MPX signal is noisy (low field strength) the VPEAK voltage increases due to the higher
noise, which is also rectified. With increasing of the VPEAK voltage the trigger threshold
increases, too. This particular gain is programmable in 4 steps (NBCT).
Figure 5.
Adaptive threshold control of noise blanker
VTH
1200 mV (00)
950 mV (01)
700 mV (10)
450 mV (11)
Noise Controlled Trig. Threshold
Min. Trig. Threshold
200 mV
8 STEPS
147 mV
0.8 V
1.5 V
V
Peak
Automatic stereo blend controlled threshold adjustment
Besides the noise controlled threshold adjustment there is an additional possibility for
influencing the noise blanker trigger threshold using the bits NBFC. This influence depends
on the stereo blend control. The point where the MPX signal starts to become noisy is fixed
by the RF part. This point is also the starting point of the normal noise-controlled trigger
adjustment. But in some cases the noise blanker can create a wrong triggering, which
create distortion, already in the region of mono/stereo transition. Therefore an opportunity to
control the VPEAK voltage by the stereo blend function it is implemented.
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Functional description
Figure 6.
TDA7541B
Stereo blend controlled threshold adjust
VPEAK
MONO
STEREO
≈ 3V
2.0V (00)
1.6V (01)
1.4V (10)
NOISE
0.8V
ATC_SB OFF (11)
noisy signal
good signal
E'
Automatic deviation controlled threshold adjustment
If the system is tuned to stations with a high deviation the noise blanker can trigger on the
higher frequencies of the modulation. To avoid this wrong behavior, which causes noise in
the output signal, the noise blanker offers a deviation-dependent threshold adjustment. By
rectifying the MPX signal a further signal representing the actual deviation is obtained. It is
used to increase the PEAK voltage. The gain of this circuit is programmable in 3 steps
(NBDC) of the stereo decoder-byte (the first step turns off the detector).
Figure 7.
Deviation controlled threshold adjust
VPEAK
[VOP]
00
2.0
01
1.5
10
1.0
11
0.8
20
32.5
45
75
Detector off
DEVIATION [KHz]
Multipath influence on noise blanker
To react on high repetitive spikes caused by a Multipath-situation, the discharge-time of the
VPEAK voltage can be decreased depending on the voltage-level at Pin MPTC. There are
two ways to do this.
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a)
Switch on the linear influence of the Multipath-Level on the PEAK-signal. In this
case the discharge slew rate is 1 V/ms. The slew rate is measured with RDischarge
= infinite and VMPTC = 2.5 V
b)
Activate a function, which switches to the 18k discharge resistor if the MultipathLevel is below 2.5 V. If multipath influence on noise blanker is switched ON than
MPF bit has to be set to 0.
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Functional description
Noise blanker in AM mode
In AM mode the noise blanker is activated if a spike on the audio signal is bigger than a fixed
threshold. In order to blank the whole spike in AM mode the hold time of the S&H circuit is
much longer than in FM mode (64 0µs -1,2 ms). It is not recommended to use the AM noise
blanker without to use the AMIF noise blanker inside the tuner.
4.3.3
Functional description of the multipath detector
Using the internal multi path detector the audible effects of a multi path condition can be
minimized. A multi path condition is detected by rectifying the 19 kHz spectrum in the field
strength signal. An external capacitor is used to define the attack- and decay-times. The
MPTC pin is used as detector output connected to a capacitor. Using this configuration an
external adaptation to the user's requirement is possible without affecting the "normal" field
strength input (FSTC) for the stereo decoder.
To keep the old value of the multi path detector during an alternative frequency jump, the
MPFAST bit can disconnect the external capacitor.
Selecting MPINT the channel separation is automatically reduced during a multipath
condition according to the voltage appearing at the MPTC pin.
To obtain a good multipath performance an adaptation is necessary. Therefore the gain of
the 19 kHz band pass is programmable in four steps (MPG) and the rectifier gain is
programmable in four steps (MPRG). The attack- and decay-times can be set by the
external capacitor value and the multipath detector charge current MPCC.
4.3.4
Quality detector
The TDA7541B offers a quality detector output, which gives a voltage representing the FMreception conditions. To calculate this voltage the MPX-noise and the multipath-detector
output are summed according to the following formula:
V Qual = 0.8 ⋅ b ⋅ ( V PEAK – 0.8 ) + a ⋅ ( V REF1 – V MPTC )
The VPEAK signal is described in noise blanker session. The factor 'a' can be programmed
from 0.6 to 1.05 (QDC) and the factor b can be programmed from 6 dB to 15 dB (QNG). The
quality output voltage can be read at the MUX pin. The MUX pin is a low impedance output
and is able to drive external circuitry as well as simply fed to an AD-converter for RDS
applications.
4.3.5
AFS control and stereo decoder mute
In case of AFS (alternative frequency search) jump it is recommended to set the stereo
decoder in mute condition (SDM) and in addition to set the SEEK mode. Since these two
bits are placed in the first written byte, this can be done in the same write cycle as the PLL
jump. The stereo decoder mute is high impedance mute, which means the charge on the
coupling capacitor will be kept. Simultaneously the pilot detector circuit of the stereo
decoder is switched into hold mode. The SEEK mode is switching the multi path detector
into fast mode. The external capacitor at MPTC is disconnected from multipath detector
which keeps the stereo blend condition, but makes the quality information in fast mode
available at the MUX pin.
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Functional description
TDA7541B
4.4
PLL and IF counter section
4.4.1
PLL frequency synthesizer block
This part contains a frequency synthesizer and a loop filter for radio tuning system. Only one
VCO is required to build a complete PLL system for FM world tuning and AM up conversion.
VCO and dividers
The varactor tuned LC oscillator together with the dividers provides the local oscillator signal
for both AM and FM front-end mixers. The VCO has an operating frequency of
approximately 160 MHz to 260 MHz. In FM mode the VCO frequency is divided (VCOD) by
1, 2 or 3. These dividers generate in-phase and quadrature-phase output signals using in
FM mixer for image rejection.
In AM mode the divided VCO frequency is additional pre-divided (AMD) by 4, 6, 8 or 10
dependent on selected AM band.
PLL frequency generation for phase comparison
The VCO divided signals applies a two modulus counter (32/33), which is controlled by a 5bit A-divider. The 5-bit register (PC0 to PC4) controls this divider. In parallel the output of the
swallow counter is connected to an 11-bit B-divider. The 11-bit PC register (PC5 to PC15)
controls this divider. Dividing range behind VCO divider:
ƒ VCOdiv = [ 32 ⋅ B + A + 32 ] ⋅ ƒ REF
Warning:
For correct operation: A ≤ 32; B ≥ A
Crystal oscillator
The crystal oscillator provides 10.25 MHz signal for conversion from IF1 to IF2 as well as
switching signals for ISS- and quality detection filter. Furthermore reference dividers
generate from adjustable crystal frequency (XTAL) reference frequencies for the tuning PLL,
IF counter and FM demodulator.
The various reference frequencies fREF of PLL (RC) can be chosen by IIC-bus.
Three state phase comparator
The phase comparator generates a phase error signal according to phase difference
between fSYN and fREF. This phase error signal drives the charge pump current generator.
Charge pump current generator
This system generator signed pulses of current. The phase error signal decides the duration
and polarity of those pulses. The current absolute values are programmable by register ICP.
In lock detector
After reaching a phase difference about lower than 40 ns the inlock detector is automatically
switching the charge-pump in low current mode (LDENA).
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Doc ID 16048 Rev 1
TDA7541B
Functional description
Low noise CMOS op-amp
An internal voltage divider at pin 19 connects the positive input of the low noise op-amp. The
charge pump output connects the negative input. This internal amplifier in cooperation with
external components can provide an active filter. The negative input is switchable to two
input pins, to increase the flexibility in application. While the high current mode is activated
LPHC output is switched on.
Antenna DAC
For tuning of FM antenna tank circuit two different modes are available (TVM). One is the
auto-alignment measurement of VCO tuning voltage with offset of 8-bit DAC (TVO). The
other one is an adjustment of 8-bit DAC independent on PLL tracking. For big differences
between VCO tuning voltage and antenna tank control voltage an additional constant offset
voltage can be switched to antenna circuit (TVO+).
4.4.2
IF counter block
The aim of IF counter is it to measure the intermediate frequency of the tuner. The input
signals are the output level of 10.7 MHz IF-limiter in FM and output level of 450 kHz IFlimiter in AM.
The grade of integration is adjustable by different measuring cycle times (IFS). The
tolerance of the accepted count value is adjustable too (EW), to reach an optimum
compromise for search speed and precision of the evaluation.
Sampling timer
A sampling timer generates the gate signal for the main counter. The basically sampling
time are in FM 6.25 kHz (tTIM = 160 s) and in AM 1 kHz (tTIM = 1 ms). This is followed by an
asynchronous divider to generate several sampling times.
Intermediate frequency main counter
This counter is an 11 - 21-bit synchronous auto reload down counter. The counter length is
automatic adjusted to the chosen sampling time and the counter mode (FM or AM).
At the start the counter will be loaded with a defined value which is an equivalent to the
divider value (tSample x fIF).
If a correct frequency is applied to the IF counter frequency input at the end of the sampling
time the main counter is changing its state. This is detected by control logic and an external
search stop output is changing from LOW to HIGH.
The IF counter is started only by the in lock information from the PLL part.
4.5
I2C bus interface
The TDA7541B supports the I2C bus protocol. This protocol defines any device that sends
data onto the bus as a transmitter, and the receiving device as the receiver. The device that
controls the transfer is a master and device being controlled is the slave. The master will
always initiate data transfer and provide the clock to transmit or receive operations.
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Functional description
TDA7541B
Data transition
Data transition on the SDA line must only occur when the clock SCL is LOW. SDA transitions
while SCL is HIGH will be interpreted as START or STOP condition.
Start condition
A start condition is defined by a HIGH to LOW transition of the SDA line while SCL is at a
stable HIGH level. This "START" condition must precede any command and initiate a data
transfer onto the bus. The device continuously monitors the SDA and SCL lines for a valid
START and will not response to any command if this condition has not been met.
Stop condition
A STOP condition is defined by a LOW to HIGH transition of the SDA while the SCL line is at
a stable HIGH level. This condition terminates the communication between the devices and
forces the bus-interface of the device into the initial condition.
Acknowledge
Indicates a successful data transfer. The transmitter will release the bus after sending 8 bits
of data. During the 9th clock cycle the receiver will pull the SDA line to LOW level to indicate
it receives the eight bits of data.
Data transfer
During data transfer the device samples the SDA line on the leading edge of the SCL clock.
Therefore, for proper device operation the SDA line must be stable during the SCL LOW to
HIGH transition.
Device addressing
To start the communication between two devices, the bus master must initiate a start
instruction sequence, followed by an eight bit word corresponding to the address of the
device it is addressing.
The most significant 6 bits of the slave address are the device type identifier.
The TDA7541B device type is fixed as "110001".
The next significant bit is used to address a particular device of the previous defined type
connected to the bus.
The state of the hardwired PIN 57 defines the state of this address bit. Using this feature up
to two devices could be connected on the same bus. When PIN 57 is connected to VCC via
an external resistor of about 82 kΩ the address bit "1" is selected. Please note: in this case
the AM part doesn't work. Otherwise the address bit "0" is selected (FM and AM is working).
Therefore a double FM tuner concept is possible.
The last bit of the start instruction defines the type of operation to be performed:
–
When set to "1", a read operation is selected
–
When set to "0", a write operation is selected
The TDA7541B connected to the bus will compare their own hardwired address with the
slave address being transmitted, after detecting a START condition. After this comparison,
the TDA7541B will generate an "acknowledge" on the SDA line and will do either a read or a
write operation according to the state of R/W bit.
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Doc ID 16048 Rev 1
TDA7541B
Functional description
Write operation
Following a START condition the master sends a slave address word with the R/W bit set to
"0". The device will generate an "acknowledge" after this first transmission and will wait for a
second word (the word address field). This 8-bit address field provides an access to any of
the 32 internal addresses. Upon receipt of the word address the TDA7541B slave device will
respond with an "acknowledge". At this time, all the following words transmitted to the
TDA7541B will be considered as Data. The internal address will be automatically
incremented. After each word receipt the TDA7541B will answer with an "acknowledge".
Read operation
If the master sends a slave address word with the R/W bit set to "1", the TDA7541B will
transmit one 8-bit data word. This data word includes the following informations.
bit0 (ISS filter, 1 = ON, 0 = OFF)
bit1 (ISS filter bandwidth, 1 = 80 kHz, 0 = 120 kHz)
bit2 (STEREO, 1 = STEREO, 0 = MONO)
bit3 (1 = PLL is locked in, 0 = PLL is locked out).
bit4 (fieldstrength indicator, 1 = lower as softmute threshold,
0 = higher as softmute threshold)
bit5 (adjacent channel indicator, 1 = adjacent channel present,
0 = no adjacent channel)
bit6 (deviation indicator, 1 = strong overdeviation present,
0 = no strong overdeviation)
bit7 (deviation indicator, 1 = overdeviation present,
0 = no overdeviation)
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Software specification
TDA7541B
5
Software specification
5.1
Chip address and overview
The interface protocol comprises:
–
start condition (S)
–
chip address byte
–
sub address byte
–
sequence of data (N bytes + Acknowledge)
–
stop condition (P)
Receive mode
S
1
1
0
0
0
1
D
0 ACK 0
0
I
A4
A3
A2
A1
A0 ACK DATABYTEACK P
0
0
1
D
1 ACK R7 R6 R5 R4
R3
R2
R1
S0 ACK
Transmission mode
S
1
1
S
= Start
P
= Stop
0
ACK = Acknowledge
D
= Device address
I
= Auto increment mode
A
= Sub address
R
= Read bit
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P
TDA7541B
Software specification
5.2
Address organization
Table 14.
Address organization
Function
Addr
D7
D6
D5
D4
D3
D2
D1
D0
T PLL charge pump
0
SEEK
T PLL counter
1
PC7
ASFC
LM
SDM
LDENA
ICP2
ICP1
ICP0
PC6
PC5
PC4
PC3
PC2
PC1
PC0
T PLL counter
2
PC15
PC14
PC13
PC12
PC11
PC10
PC9
PC8
T TV
3
TVO7
TVO6
TVO5
TVO4
TVO3
TVO2
TVO1
TVO0
T TV/IF counter
4
FMON
EW6
EW5
IFS4
IFS3
ISSENA
TVM
TVO+
T PLL divider
5
AMD7
AMD6
RC5
RC4
RC3
VCOD2
VCOD1
VCOD0
T AGC
6
LNA7
LNA6
DAGC5
DAGC4
IFAGC3
IFAGC2
RFAGC1
RFAGC0
T Quality AC
7
TISS7
TISS6
TISS5
ACTH4
ACTH3
ACF
BWDEF
ISSBW
T Quality ACM/MP
8
MPTH7
MPTH6
MPAC
MPENA
ACMD
T Quality DEV
9
ISSM
DTH6
DTH5
DWTH4
DWTH3
TDEV2
TDEV1
TDEV0
T Quality MUX/FSU
10
SSTH7
SSTH6
SSTH5
SSTH4
SACCT
SACCE
MUX1
MUX0
T Weak signal mute
11
WMD7
WMD6
WMD5
WMTH4
WMTH3
WMTH2
WBON
ISSON
ACMTH2 ACMTH1
ACMTH0
T AM IF NB
12
IFAGCS
AINT6
AINT5
AINTH4
AINTH3
AINTH2
AINTH1
AINENA
T XTAL adjust
13
SL7
SL6
SL5
XTAL4
XTAL3
XTAL2
XTAL1
XTAL0
T IF adjust
14
IF1G7
IF1G6
IF2Q5
IF2Q4
IF2A3
IF2A2
IF2A1
IF2A0
T IQ adjust/Switch
15
DSB7
DSB6
SWM
SW
PH3
PH2
PH1
PH0
T FM keying AGC
16
FSWO7
FSWO6
RFK
KAGC4
KAGC3
KAGC2
ODCUR
ODENA
SD Roll off
17
LG7
LG6
LG5
LG4
ROC3
ROC2
ROC1
ROC0
SD Stereo blend
18
AMCF7
AMCF6
AMCF5
ASI
PTH
SBC2
SBC1
SBC0
SD High cut
19
DEEMP
HCLT6
HCLT5
HCHT4
HCHT3
HCMAX2 HCMAX1
HCENA
SD MP
20
MS
MPFAST
MPINT
MPCC
MPRG3
MPRG2
MPG1
MPG0
SD quality
21
NBFC7
NBFC6
NBDC5
NBDC4
QNG3
QNG2
QDC1
QDC0
SD Audio NB I
22
NBCT7
NBCT6
NBLT5
NBLT4
NBLT3
NBT2
NBT1
NBENA
SD Audio NB II
23
ADSEL
PCM
VCON
NBSMP
NBMP
NBRR2
NBRR1
NBPC
SD Testing
24
-
-
-
-
-
-
-
-
T PLL/IFC Testing
25
EWEXP
IFSEXP
1
1
1
1
1
1
T Testing
26
-
-
-
-
-
-
-
-
T Testing
27
-
-
-
-
-
-
-
-
T Testing
28
-
-
-
-
-
-
-
-
T Testing
29
-
-
-
-
-
-
-
-
Not used
30
-
-
-
-
-
-
-
-
Not used
31
-
-
-
-
-
-
-
-
T
Tuner
SD
Stereo decoder
Data bytes which are unused or dedicated for testing only don't need to be written, because
they are set internally to FEH (power on reset condition). But if somebody it writing these
bytes they must be written to FEH, otherwise some malfunction of the chip can happen.
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Software specification
5.3
TDA7541B
Control register function
Table 15.
I2C control bit description
Register
Name
ACF
ACMD
ACMTH
Adjacent channel detector filter select
Adjacent channel mute depth
Adjacent channel mute threshold
ACTH
Adjacent channel detector threshold
ADSEL
Additional selectivity
AINENA
AM IF noise blanker enable
AINT
AM IF noise blanking time
AINTH
AM IF noise blanker threshold
AMCF
Stereo decoder attenuation @ 3.5 kHz
AMD
AM VCO pre-divider
ASFC
Alternative station frequency check in FM (AGC and weak signal mute on hold)
ASI
BWDEF
DAGC
Audio signal inversion
Enables bit ISSBW for ISS bandwidth control
AM narrow band AGC threshold
DEEMP
Stereo decoder de-emphasis
DSB
FM demodulator spike blanker
DTH
Deviation detector threshold for ISS filter “OFF”
DWTH
Deviation detector threshold for ISS filter 120 kHz
EW
IF counter frequency error window
EWEXP
Expanded IF counter error window
FMON
Internal switch FM-AM mode
FSWO
Weighted fieldstrength with offset adjust
HCENA
High cut enable
HCHT
Start level high cut
HCLT
Stop level high cut
HCMAX
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Function
Maximum high cut depth
ICP
Charge pump current tuner PLL
IF1G
IF1 Amplifier Gain
IF2A
IF2 LC band pass fine adjust
IF2Q
IF2 LC band pass quality adjust
IFAGC
FM/AM IF AGC threshold
IFAGCS
AM IFAGC threshold shift
Doc ID 16048 Rev 1
TDA7541B
Software specification
Table 15.
I2C control bit description (continued)
Register
Name
IFS
Function
IF counter sampling time
IFSEXP
Expanded IF counter sampling time
ISSBW
ISS filter band width select
ISSENA
ISS filter enable
ISSON
ISS filter control mode
ISSM
ISS filter application mode
KAGC
FM keying AGC
LDENA
Lock detector enable tuner PLL
LG
Stereo decoder level gain adjust
LM
FM local mode enable
LNA
AM LNA Pin/FET mode
MPAC
Influence tuner multi path detection on adjacent channel behavior
MPCC
Stereo decoder multi path detector charge current
MPENA
Tuner multi path detector influence on adjacent channel enable
MPFAST Fast mode of multi path information at quality pin
MPG
Multi path detector gain
MPINT
Stereo decoder multi path internal influence enable
MPRG
Stereo decoder multi path detector rectifier gain
MPTH
Tuner multi path detector threshold
MS
MUX
NBENA
Mono/Stereo switch fixed (“Forced Mono”)
Output multiplexer for MUX pin
Audio noise blanker enable
NBCT
Audio noise blanker noise controlled threshold
NBDC
Audio noise blanker deviation control
NBFC
Audio noise blanker field strength control
NBLT
Audio noise blanker low threshold
NBMP
Stereo decoder multi path influence on peak discharge current
NBPC
Audio noise blanker peak charge current
NBRR
Audio noise blanker rectifier discharge resistor
NBSMP
NBT
Strong multi path influence on audio noise blanker
Audio noise blanker time constant
ODCUR
Current for over deviation correction
ODENA
Over deviation correction enable
PC
Tuner PLL counter
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Software specification
Table 15.
TDA7541B
I2C control bit description (continued)
Register
Name
PCM
Pilot cancellation mode
PH
IQ mixer phase adjust
PTH
Pilot detector threshold
QDC
Stereo decoder quality detector coefficient
QNG
Stereo decoder quality noise gain
RC
RFAGC
Tuner PLL reference counter
FM/AM RF AGC threshold
RFK
FM RF keying AGC
ROC
Stereo decoder roll off compensation
SACCT
Strong adjacent channel correction threshold
SACCE
Strong adjacent channel correction enable
SBC
Stereo blend control
SDM
Stereo decoder mute enable
SEEK
FM: FMON = 1, ISS time constant change / AM: FMON = 0, AGC2 time constant change
SL
SSTH
SW
S meter slope
Field strength threshold for seek stop
Free programmable switch
SWM
Free programmable switch mode
TDEV
Time constant for deviation detector
TISS
Time constant for ISS filter “ON”/”OFF”
TVM
Tuning voltage offset mode
TVO
Tuning voltage offset
TVO+
Additional fixed tuning voltage offset
VCOD
Tuner VCO divider
VCON
STD VCO “ON/OFF”
WBON
Weather band mode (ISS filter band width 24 kHz)
WMD
Weak signal mute depth
WMTH
Weak signal mute start point threshold
XTAL
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Function
Xtal frequency fine adjust
Doc ID 16048 Rev 1
TDA7541B
Software specification
5.4
Data byte specification
Table 16.
Subaddress description
MSB
LSB
Function
-
-
-
-
I
A4
A3
A2
A1
A0
0
0
0
0
0
Charge pump control
1
0
1
1
1
Audio noise blanker II
-
-
-
-
-
-
0
-
-
Page mode “OFF”
1
Table 17.
Page mode enable
Addr 0 TPLL charge pump control (0Bh)
MSB
LSB
Function
d7
d6
d5
d4
d3
d2
d1
d0
0
0
0
Charge pump current = 50 µA
0
0
1
Charge pump current = 0.5 mA
0
1
0
Charge pump current = 1 mA
0
1
1
Charge pump current = 1.5 mA
1
1
0
Charge pump current = 3 mA
1
1
1
Charge pump current = 3.5 mA
-
-
-
ICP<2:0>
-
-
-
-
-
LDENA
-
-
-
-
0
1
Lock detector disable
Lock detector enable
SDM
-
-
-
0
-
-
-
-
1
Stereo decoder mute disable
Stereo decoder mute enable
LM
-
-
0
-
-
-
-
-
1
Local mode disable
Local mode enable
ASFC
-
0
-
-
-
-
-
-
1
Weak signal mute and AGC normal mode in FM
Weak signal mute and AGC on hold in FM mode
SEEK
0
1
-
-
-
-
-
-
-
ISS time constant at pin 30 available, AM SEEK “OFF”
ISS time constant at pin 31 available, AM SEEK “ON”
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Software specification
Table 18.
TDA7541B
Addr 1 TPLL Counter 1 (LSB)
MSB
LSB
Function
d7
d6
d5
d4
d3
d2
d1
d0
PC<7:0>
0
0
0
0
0
0
0
0
LSB = 0
0
0
0
0
0
0
0
1
LSB = 1
0
0
0
0
0
0
1
0
LSB = 2
1
1
1
1
1
1
0
0
LSB = 252
1
1
1
1
1
1
0
1
LSB = 253
1
1
1
1
1
1
1
0
LSB = 254
1
1
1
1
1
1
1
1
LSB = 255
Table 19.
Addr 2 TPLL Counter 2 (MSB)
MSB
LSB
Function
d7
d6
d5
d4
d3
d2
d1
d0
PC<15:8>
0
0
0
0
0
0
0
0
MSB = 0
0
0
0
0
0
0
0
1
MSB = 256
0
0
0
0
0
0
1
0
MSB = 512
1
1
1
1
1
1
0
0
MSB = 64768
1
1
1
1
1
1
0
1
MSB = 65024
1
1
1
1
1
1
1
0
MSB = 65280
1
1
1
1
1
1
1
1
MSB = 65536
Note:
Swallow mode: fVCO/fSYN = LSB + MSB + 32
Table 20.
Addr 3 TV(00h)
MSB
LSB
Function
d7
d6
d5
d4
d3
d2
d1
d0
TVO<7:0>
0
0
0
0
0
0
0
Tuning Voltage Offset = 0mV
0
0
0
0
0
0
1
TVO = 25 mV
0
0
0
0
0
1
0
TVO = 50 mV
1
1
1
1
1
1
0
TVO = 3150 mV
1
1
1
1
1
1
1
TVO = 3175 mV
-
-
-
-
-
-
-
0
1
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-TVO
+TVO
Doc ID 16048 Rev 1
TDA7541B
Table 21.
Addr25
Software specification
Addr 4 TV/IF Counter (FM ACh, AM 1Ch)
MSB
LSB
Function
d7
d6
d7
d6
d5
d4
d3
d2
d1
d0
TVO+
-
-
-
-
-
-
-
-
-
0
Disable additional TV offset
1
Enable additional TV offset + 3.175 V
TVM
-
-
-
-
-
-
-
-
0
-
1
TV is tracking with PLL
TV is independing on PLL
ISSENA
-
-
-
-
-
-
-
0
-
-
1
ISS Filter switched off (bypass of filter, wide)
ISS filter control enable
IFS<4:3>
-
1
0
0
tSample = 20.48 ms (FM) 128 ms (AM)
1
0
1
tSample = 10.24 ms (FM) 64 ms (AM)
1
1
0
tSample = 5.12 ms (FM) 32 ms (AM)
1
1
0
0
0
tSample = 1.28 ms (FM) 8 ms (AM)
0
0
1
tSample = 0.64 ms (FM) 4 ms (AM)
0
1
0
tSample = 0.32 ms (FM) 2 ms (AM)
0
1
1
tSample = 0.16 ms (FM) 1 ms (AM)
1
-
-
-
-
-
-
tSample = 2.56 ms (FM) 16 ms (AM)
EW<6:5>
1
0
0
Δf = 12.5 kHz (FM) 2 kHz (AM)
1
0
1
Δf = 25 kHz (FM) 4 kHz (AM)
1
1
0
Δf = 50 kHz (FM) 8 kHz (AM)
1
1
0
0
0
Not valid
0
0
1
Not valid
0
1
0
Not valid
0
1
1
Δf = 6.25 kHz (FM) 1 kHz (AM)
1
-
-
-
-
-
-
-
Δf = 100kHz (FM) 16kHz (AM)
FMON
-
-
0
-
-
-
-
-
-
-
1
Select AM mode
Select FM mode
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Software specification
Table 22.
TDA7541B
Addr 5 TPLL Divider (FM 3Dh, AM 2Dh)
MSB
LSB
Function
d7
d6
d5
d4
d3
d2
d1
d0
VCOD<2:0>
-
-
-
-
-
0
0
not valid (only for testing)
0
1
VCO frequency divided by 2
1
0
VCO frequency divided by 3
1
1
original VCO frequency
0
VCO ”I” signal 0 degree
1
VCO “I” signal 180 degree
RC<5:3>
-
0
1
1
1
0
0
-
PLL reference frequency 2 kHz
PLL reference frequency 9 kHz
-
-
-
1
0
1
PLL reference frequency 10 kHz (AM)
1
1
0
PLL reference frequency 25 kHz
1
1
1
PLL reference frequency 50 kHz (FM)
AMD<7:6>
0
0
0
1
1
0
AM VCO predivider ratio 6
1
1
AM VCO predivider ratio 4
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AM VCO predivider ratio 10
-
-
-
-
-
-
AM VCO predivider ratio 8
Doc ID 16048 Rev 1
TDA7541B
Software specification
Table 23.
Addr 6 AGC (FM 06h, AM 2Ah)
Addr12 MSB
LSB
Function
d7
d7
d6
d5
d4
d3
d2
d1
d0
RFAGC<1:0>
-
-
-
-
-
-
-
0
0
RFAGC threshold FM V8-10= 80 dBµV, AM V3= 92 dBµV
0
1
RFAGC threshold FM V8-10= 84 dBµV, AM V3= 99 dBµV
1
0
RFAGC threshold FM V8-10= 88 dBµV, AM V3= 102 dBµV
1
1
RFAGC threshold FM V8-10= 92 dBµV, AM V3= 104 dBµV
IFAGC<3:2>
1
0
0
IFAGC threshold FM V61= 82 dBµV, AM V61= 89 dBµV
1
0
1
IFAGC threshold FM V61= 88 dBµV, AM V61= 95 dBµV
1
1
0
IFAGC threshold FM V61= 91 dBµV, AM V61= 99 dBµV
1
1
0
0
0
IFAGC threshold FM V61= 82 dBµV, AM V61= 79 dBµV
0
0
1
IFAGC threshold FM V61= 88 dBµV, AM V61= 85 dBµV
0
1
0
IFAGC threshold FM V61= 91 dBµV, AM V61= 89 dBµV
0
1
1
IFAGC threshold FM V61= 94 dBµV, AM V61= 92 dBµV
1
-
-
-
-
-
-
IFAGC threshold FM V61= 94 dBµV, AM V61= 102 dBµV
DAGC<5:4>
-
-
-
DAGC V56= 86 dBµ
0
0
0
1
1
0
DAGC V56= 95 dBµ
1
1
DAGC V56= 98 dBµ
-
-
-
-
DAGC V56= 91 dBµ
LNA<7:6>
-
I4 = 400 µA, V54 = 4.5 V, AM LNA Pin/FET mode ”OFF”
0
0
0
1
1
0
I4 = 400 µA + 100 µA, V54 = 3.5 V
1
1
I4 = 400 µA + 100 µA, V54 = 3.5 V
-
-
-
-
-
-
I4 = 400 µA + 50 µA, V54 = 3.5 V
Doc ID 16048 Rev 1
51/77
Software specification
Table 24.
TDA7541B
Addr 7 Quality AC (FM 50h)
MSB
LSB
Function
d7
d6
d5
d4
d3
d2
d1
d0
ISSBW
-
-
-
-
-
-
-
0
ISS filter fixed band width 120 kHz
1
ISS filter fixed band width 80 kHz
BWDEF
-
-
-
-
-
-
0
-
1
Disable bit ISSBW for ISS filter band width control
Enable bit ISSBW for ISS filter band width control
ACF
-
-
-
-
-
0
-
-
1
AC highpass frequency 100 kHz
AC bandpass frequency 100 kHz
ACTH<4:3>
-
-
-
0
0
AC detector threshold 0.35 V
0
1
1
0
AC detector threshold 0.55 V
1
1
AC detector threshold 0.65 V
-
-
-
AC detector threshold 0.45 V
TISS<7:5>
0
0
0
discharge current 1 µA, charge current mid 74 µA, narrow 124 µA
0
0
1
discharge current 3 µA, charge current mid 72 µA, narrow 122 µA
0
1
0
0
1
1
discharge current 7 µA, charge current mid 68 µA, narrow 118 µA
1
1
1
discharge current 15 µA, charge current mid 60 µA, narrow 110 µA
52/77
-
-
-
-
-
discharge current 5 µA, charge current mid 70 µA, narrow 120 µA
Doc ID 16048 Rev 1
TDA7541B
Table 25.
Software specification
Addr 8 Quality ACM/MP (FM 6Ah)
MSB
LSB
Function
d7
d6
d5
d4
d3
d2
d1
d0
ACMTH<2:0>
-
-
-
-
0
0
0
AC mute threshold 60 mV
0
0
1
AC mute threshold 90 mV
0
1
0
AC mute threshold 150 mV
1
1
0
AC mute threshold 240 mV
1
1
1
AC mute OFF
-
ACMD
-
-
-
-
0
-
-
-
1
Adjacent channel mute depth -4 dB
Adjacent channel mute depth -6 dB
MPENA
-
-
-
0
-
-
-
-
1
Multipath control “ON”
Multipath control “OFF”
MPAC
-
-
0
-
-
-
-
-
Multipath eliminates ac (MPENA = 0)
Multipath eliminates ac and ac+ (MPENA = 0)
1
MPTH<7:6>
0
0
MP threshold 0.50 V
0
1
1
0
MP threshold 1.00 V
1
1
MP threshold 1.25 V
-
-
-
-
-
-
MP threshold 0.75 V
Doc ID 16048 Rev 1
53/77
Software specification
Table 26.
TDA7541B
Addr 9 Quality Dev (FM 49h)
MSB
LSB
Function
d7
d6
d5
d4
d3
d2
d1
d0
TDEV<2:0>
-
-
-
-
-
0
0
0
charge current 39 µA, discharge current 1 µA
0
0
1
charge current 38 µA, discharge current 2 µA
0
1
0
charge current 37 µA, discharge current 3 µA
0
1
1
charge current 36 µA, discharge current 4 µA
1
1
0
charge current 33 µA, discharge current 7 µA
1
1
1
charge current 32 µA, discharge current 8 µA
DWTH<4:3>
-
-
-
0
0
DEV threshold for ISS narrow/wide 20 kHz
0
1
1
0
DEV threshold for ISS narrow/wide 40 kHz
1
1
DEV threshold for ISS narrow/wide 50 kHz
-
-
-
DEV threshold for ISS narrow/wide 30 kHz
DTH<6:5>
-
0
0
DEV threshold for ISS filter “OFF” ratio 1.5
0
1
1
0
DEV threshold for ISS filter “OFF” ratio 1.3
1
1
DEV threshold for ISS filter “OFF” ratio 1
-
-
-
-
-
DEV threshold for ISS filter “OFF” ratio 1.4
ISSM
0
1
54/77
-
-
-
-
-
-
-
ISS filter application mode 1
ISS filter application mode 2
Doc ID 16048 Rev 1
TDA7541B
Table 27.
Software specification
Addr 10 Quality MUX/FSU (FM 0Eh, AM 0Fh)
MSB
LSB
Function
d7
d6
d5
d4
d3
d2
d1
d0
MUX<1:0>
-
-
-
-
-
-
0
0
Detected multipath information at PIN 23
0
1
Detected adjacent channel information at PIN 23
1
0
Quality information stereo decoder at PIN 23
1
1
FMON=1: Stereo indication at PIN 23
FMON=0: AM IF2 signal at PIN 23
-
-
-
-
-
0
1
-
-
SACCE
Strong adjacent channel correction disable
Strong adjacent channel correction enable
-
-
-
-
0
1
-
-
-
SACCT
Strong adjacent channel correction threshold = 2.9 V
Strong adjacent channel correction threshold = 3.0V
0
0
0
0
0
0
0
1
0
0
1
0
0
0
1
1
SSTOP = H if IFC = H & FS >
0
1
0
0
SSTOP = H if IFC = H & FS >
1
1
1
1
SSTOP = H if IFC = H & FS > (FM: 4.1 V / AM: 4.8 V)
SSTH<7:4>
Table 28.
SSTOP = IFC (IF counter status)
SSTOP = H if IFC = H & FS > (FM: 0.6 V / AM: 1.2 V)
-
-
-
-
SSTOP = H if IFC = H & FS >
Addr 11 Weak Signal Mute (FM A8h)
MSB
LSB
Function
d7
d6
d5
d4
d3
d2
d1
d0
ISSON
-
-
-
-
-
-
-
0
ISS filter internal control
1
ISS filter forced “ON”
-
Weather band disable
WBON
-
-
-
-
-
-
0
1
Weather band enable
WMTH<4:2>
-
-
-
0
0
0
Startpoint mute 0
0
0
1
Startpoint mute 1
0
1
0
1
1
0
1
1
1
-
-
Startpoint mute 2
Startpoint mute 6
Startpoint mute 7
WMD<7:5>
0
0
0
0
0
1
Mute depth 0
1
0
1
Mute depth 5
1
1
1
Mute depth 7
-
-
-
-
-
Mute depth 1
Doc ID 16048 Rev 1
55/77
Software specification
Table 29.
TDA7541B
Addr 12 AM IF NB (AM B1h)
MSB
LSB
Function
d7
d6
d5
d4
d3
d2
d1
d0
-
-
-
-
-
-
-
0
1
-
-
0
0
0
0
1
1
0
0
1
1
0
1
0
1
0
0
0
1
0
0
0
1
0
1
-
0
0
1
1
0
1
0
1
-
-
-
-
-
-
-
-
-
-
-
-
-
-
0
1
Table 30.
AINENA
AM IF noise blanker disable
AM IF noise blanker enable
AINTH<4:1>
not recommended
not recommended
AM IF NB Threshold 50 mV
AM IF NB Threshold 62.5 mV
AM IF NB Threshold 100 mV
AM IF NB Threshold 187.5 mV
AINT<6:5>
AM IF NB Time 8 µs
AM IF NB Time 11 µs
AM IF NB Time 14 µs
AM IF NB Time 17 µs
IFAGCS
Enable AM IFAGC threshold shift down (check address6)
Disable AM IFAGC threshold shift down
Addr 13 XTAL adjust(80h)
MSB
LSB
Function
d7
d6
d5
d4
d3
d2
d1
d0
XTAL<4:0>
-
-
-
0
0
0
0
0
CLoad 0pF
0
0
0
0
1
CLoad 0.75 pF
0
0
0
1
0
CLoad 1.5 pF
0
0
0
1
1
CLoad 2.25 pF
0
0
1
0
0
CLoad 3 pF
1
1
1
1
0
CLoad 22.5 pF
1
1
1
1
1
CLoad 23.25 pF
SL<7:5>
0
0
0
S meter slope FM = 0.75 V/20 dB, AM = 1.61 V/20 dB
0
0
1
S meter slope FM = 0.80 V/20 dB, AM = 1.75 V/20 dB
0
1
0
0
1
1
S meter slope FM = 0.85 V/20 dB, AM = 1.89 V/20 dB
-
-
-
-
-
S meter slope FM = 0.90 V/20 dB, AM = 1.98 V/20 dB
1
0
0
S meter slope FM = 0.95 V/20 dB, AM = 2.04 V/20 dB
1
0
1
S meter slope FM = 1.0 V/20 dB, AM = 2.1 V/20 dB
1
1
0
S meter slope FM = 1.05 V/20 dB, AM = 2.15 V/20 dB
1
1
1
S meter slope FM = 1.1 V/20 dB, AM = 2.20 V/20 dB
56/77
Doc ID 16048 Rev 1
TDA7541B
Table 31.
Software specification
Addr 14 IF2 adjust (FM E8h, AM 08h)
MSB
LSB
Function
d7
d6
d5
d4
d3
d2
d1
d0
IF2A<3:0>
-
-
-
-
0
0
0
0
Cadj 0 pF
0
0
0
1
Cadj 2,2 pF
0
0
1
0
Cadj 4,4 pF
0
0
1
1
Cadj 6,6 pF
0
1
0
0
Cadj 8,8 pF
1
0
0
0
Cadj 17,6 pF
1
1
1
1
Cadj 33 pF
IF2Q<5:4>
-
-
0
0
no Rint, AM Q=28/gain=26 dB, FM Q=28/gain=16 dB
0
1
1
0
Rint =4,1 kOhm, FM Q=2,5/gain=14 dB, BW=180 kHz
1
1
Rint =3,3 kOhm, FM Q=2,05/gain=14 dB, BW=220 kHz
-
-
-
-
Rint =5 kOhm, FM Q=3/gain=14 dB, BW=150 kHz
IF1G<7:6>
0
0
IF1 gain 9 dB (AM)
0
1
1
0
IF1 gain 17 dB
1
1
IF1 gain 21 dB (FM)
-
-
-
-
-
-
IF1 gain 12 dB
Doc ID 16048 Rev 1
57/77
Software specification
Table 32.
TDA7541B
Addr 15 IQ adjust / Switch (FM E7h)
MSB
LSB
Function
d7
d6
d5
d4
d3
d2
d1
d0
PH<3:0>
-
-
-
-
0
0
0
0
-7 degree
0
0
0
1
-6 degree
0
0
1
0
-5 degree
0
1
1
1
0 degree
1
0
0
0
1 degree
1
0
0
1
2 degree
1
1
1
0
7 degree
1
1
1
1
8 degree
SW
-
-
-
0
-
-
-
-
1
S1 LOW output voltage
S1 HIGH output voltage
SWM
-
-
0
-
-
-
-
-
1
S1 emitter output available
S1 open collector output available
DSB<7:6>
0
0
0
1
1
0
Threshold for FM demodulator spike cancellation 400 mV
1
1
Threshold for FM demodulator spike cancellation 520 mV
58/77
FM demodulator spike cancellation ”OFF”
-
-
-
-
-
-
Threshold for FM demodulator spike cancellation 630 mV
Doc ID 16048 Rev 1
TDA7541B
Table 33.
Software specification
Addr 16 FM keying AGC (FM 1Dh)
MSB
LSB
Function
d7
d6
d5
d4
d3
d2
d1
d0
ODENA
-
-
-
-
-
-
-
0
Over deviation correction disable
1
Over deviation correction enable
ODCUR
-
-
-
-
-
-
0
-
1
over deviation correction current max=45 µA
over deviation correction current max=90 µA
KAGC<4:2>
-
-
-
0
0
0
KAGC threshold 3,60* V48 /5
0
0
1
KAGC threshold 3,65* V48 /5
0
1
0
KAGC threshold 3,70* V48 /5
0
1
1
1
0
0
KAGC threshold 3,80* V48 /5
1
0
1
KAGC threshold 3,85* V48 /5
1
1
0
KAGC threshold 3,90* V48 /5
1
1
1
Keying AGC “OFF”
-
-
KAGC threshold 3,75* V48 /5
RFK
-
-
0
-
-
-
-
-
1
RF keying AGC OFF
RF keying AGC ON
FSWO<7:6>
0
0
FSW offset OFF
0
1
1
0
FSW offset = -150 mV
1
1
FSW offset = -192 mV
-
-
-
-
-
-
FSW offset = -75 mV
Doc ID 16048 Rev 1
59/77
Software specification
Table 34.
TDA7541B
Addr 17 Roll off / Level gain (77h)
MSB
LSB
Function
d7
d6
d5
d4
d3
d2
d1
d0
ROC<3:0>
-
-
-
-
0
0
0
0
Roll-Off compensation 25.8 %
0
0
0
1
Roll-Off compensation 24.0 %
0
0
1
0
Roll-Off compensation 22.2 %
0
0
1
1
Roll-Off compensation 20.5 %
0
1
0
0
Roll-Off compensation 18.8 %
0
1
0
1
Roll-Off compensation 17.1 %
0
1
1
0
Roll-Off compensation 15.4 %
0
1
1
1
Roll-Off compensation 13.8 %
1
0
0
0
Roll-Off compensation 12.2 %
1
0
0
1
Roll-Off compensation 10.6 %
1
0
1
0
Roll-Off compensation 9.0 %
1
0
1
1
Roll-Off compensation 7.5 %
1
1
0
0
Roll-Off compensation 6.0 %
1
1
0
1
Roll-Off compensation 4.5 %
1
1
1
0
Roll-Off compensation 3,0 %
1
1
1
1
Roll-Off compensation 1.6 %
LG<7:4>
0
0
0
0
Level gain 0 dB
0
0
0
1
Level gain 0.55 dB
0
0
1
0
0
1
1
1
Level gain 3.85 dB
1
1
1
1
Level gain 8.25 dB
60/77
-
-
-
-
Level gain 1.10 dB
Doc ID 16048 Rev 1
TDA7541B
Table 35.
Software specification
Addr 18 SD Stereoblend / AM corner frequency (0Dh)
MSB
LSB
Function
d7
d6
d5
d4
d3
d2
d1
d0
SBC<2:0>
-
-
-
-
-
0
0
0
Stereoblend control at 29 % REF5V
0
0
1
Stereoblend control at 33 % REF5V
0
1
0
Stereoblend control at 38 % REF5V
0
1
1
Stereoblend control at 42 % REF5V
1
0
0
Stereoblend control at 46 % REF5V
1
0
1
Stereoblend control at 50 % REF5V
1
1
0
Stereoblend control at 54 % REF5V
1
1
1
Stereoblend control at 58 % REF5V
PTH
-
-
-
-
0
-
-
-
1
Pilot threshold high
Pilot threshold low
ASI
-
-
-
0
-
-
-
-
1
Audio inverter “OFF”
Audio inverter “ON”
AMCF<7:5>
0
0
0
AM attenuation @ 3.5 kHz = 8.4 dB
0
0
1
AM attenuation @ 3.5 kHz = 8.0 dB
0
1
0
1
1
0
AM attenuation @ 3.5 kHz = 4.4 dB
1
1
1
AM attenuation @ 3.5 kHz = 3.6 dB
-
-
-
-
-
AM attenuation @ 3.5 kHz = 7.3 dB
Doc ID 16048 Rev 1
61/77
Software specification
Table 36.
TDA7541B
Addr 19 SD High cut (2Fh)
MSB
LSB
Function
d7
d6
d5
d4
d3
d2
d1
d0
HCENA
-
-
-
-
-
-
-
0
High cut “OFF”
1
High cut “ON”
HCMAX<2:1>
-
-
-
-
-
0
0
Maximum high cut 10 dB
0
1
1
0
Maximum high cut 7.5 dB
1
1
Maximum high cut 8.5 dB
-
Maximum high cut 5.5 dB
HCHT<4:3>
-
-
-
0
0
Start level high cut @ 42 % REF5V
0
1
1
0
Start level high cut @ 58 % REF5V
1
1
Start level high cut @ 66 % REF5V
-
-
-
Start level high cut @ 50 % REF5V
HCLT<6:5>
-
0
0
Stop level high cut @ 11 % VHCHT
0
1
1
0
Stop level high cut @ 25.7 % VHCHT
1
1
Stop level high cut @ 33 % VHCHT
-
-
-
-
-
Stop level high cut @ 18.3 % VHCHT
DEEMP
0
1
62/77
-
-
-
-
-
-
-
De-emphasis 50 µs
De-emphasis 75 µs
Doc ID 16048 Rev 1
TDA7541B
Table 37.
Software specification
Addr 20 SD MP (FM 97h, AM 3Fh)
MSB
LSB
Function
d7
d6
d5
d4
d3
d2
d1
d0
MPG<1:0>
-
-
-
-
-
-
0
0
Multipath detector gain =6 dB
0
1
Multipath detector gain =12 dB
1
0
Multipath detector gain =9 dB
1
1
Multipath detector gain =10.5 dB
MPRG<3:2>
-
-
-
-
0
0
Multipath detector rectifier gain =7,6 dB
0
1
1
0
Multipath detector rectifier gain =0d B
1
1
Multipath detector rectifier gain disabled
-
-
Multipath detector rectifier gain =4,6 dB
MPCC
-
-
-
0
-
-
-
-
1
Multipath detector charge current =0,8 µA
Multipath detector charge current =0,4 µA
MPINT
-
-
0
-
-
-
-
-
1
Multipath detector internal influence “ON”
Multipath detector internal influence “OFF”
MPFAST
0
-
-
-
-
-
-
1
External time constant (MPTC) enable
External time constant (MPTC) disable
MS
0
1
-
-
-
-
-
-
-
Forced MONO
MONO/STEREO switch automatically
Doc ID 16048 Rev 1
63/77
Software specification
Table 38.
TDA7541B
Addr 21 SD Quality (FFM 7Ah, AM FAh)
MSB
LSB
Function
d7
d6
d5
d4
d3
d2
d1
d0
QDC<1:0>
-
-
-
-
-
-
0
0
Quality detector coefficient a=0,6
0
1
Quality detector coefficient a=0,75
1
0
Quality detector coefficient a=0,9
1
1
Quality detector coefficient a=1,05
QNG<3:2>
-
-
-
-
0
0
Quality noise gain =6 dB
0
1
1
0
Quality noise gain =12 dB
1
1
Quality noise gain =15 dB
-
-
Quality noise gain =9 dB
NBDC<5:4>
-
-
0
0
Noise blanker deviation adjust 2.0 V
0
1
1
0
Noise blanker deviation adjust 1.0 V
1
1
Noise blanker deviation adjust “OFF”
-
-
-
-
Noise blanker deviation adjust 1.5 V
NBFC<7:6>
0
0
0
1
1
0
Noise blanker field strength adjust 1.4 V
1
1
Noise blanker field strength adjust “OFF”
64/77
Noise blanker field strength adjust 2.0 V
-
-
-
-
-
-
Noise blanker field strength adjust 1.6 V
Doc ID 16048 Rev 1
TDA7541B
Table 39.
Software specification
Addr 22 SD NB I (FM 05h, AM 04h)
MSB
LSB
Function
d7
d6
d5
d4
d3
d2
d1
d0
NBENA
-
-
-
-
-
-
-
0
Audio noise blanker “OFF”
1
Audio noise blanker “ON”
NBT<2:1>
-
-
-
-
-
0
0
Audio noise blanking time 38 µs
0
1
1
0
Audio noise blanking time 32 µs
1
1
Audio noise blanking time 22 µs
-
Audio noise blanking time 25,5 µs
NBLT<5:3>
-
-
0
0
0
Noise blanker low threshold 280 mV
0
0
1
Noise blanker low threshold 261 mV
0
1
0
Noise blanker low threshold 242 mV
0
1
1
1
0
0
Noise blanker low threshold 204 mV
1
0
1
Noise blanker low threshold 185 mV
1
1
0
Noise blanker low threshold 166 mV
1
1
1
Noise blanker low threshold 147 mV
-
-
-
Noise blanker low threshold 223 mV
NBCT<7:6>
0
0
Noise blanker noise controlled threshold 1200 mV
0
1
1
0
Noise blanker noise controlled threshold 700 mV
1
1
Noise blanker noise controlled threshold 450 mV
-
-
-
-
-
-
Noise blanker noise controlled threshold 950 mV
Doc ID 16048 Rev 1
65/77
Software specification
Table 40.
TDA7541B
Addr 23 SD NB II (FM E2h, AM C2h)
MSB
LSB
Function
d7
d6
d5
d4
d3
d2
d1
d0
NBPC
-
-
-
-
-
-
-
0
Noise blanker peak charge current low
1
Noise blanker peak charge current high
NBRR<2:1>
-
-
-
-
-
0
0
Noise rectifier discharge resistor = infinite
0
1
1
0
Noise rectifier discharge resistor =33 k
1
1
Noise rectifier discharge resistor =18k
-
Noise rectifier discharge resistor =56 k
NBMP
-
-
-
-
0
-
-
-
1
Multipath influence on peak discharge “OFF”
Multipath influence on peak discharge “ON” (-3 V/ms)
NBSMP
-
-
-
0
-
-
-
-
1
Strong multipath influence on peak discharge “OFF”
Strong multipath influence on peak discharge “ON”
VCON
-
-
0
-
-
-
-
-
1
Stereo decoder VCO “OFF”
Stereo decoder VCO “ON”
PCM
-
0
-
-
-
-
-
-
1
Pilot cancellation mode: always
Pilot cancellation mode: if pilot > pilot threshold
ADSEL
0
1
66/77
-
-
-
-
-
-
-
Additional selectivity OFF
Additional selectivity ON
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TDA7541B
Table 41.
Software specification
Addr 24, 26, 27, 28, 29 testing (FEh)
MSB
LSB
Function
d7
d6
d5
d4
d3
d2
d1
d0
1
1
1
1
1
1
1
0
Table 42.
Only for testing
Addr 25 Testing (FEh)
MSB
LSB
Function
d7
d6
d5
d4
d3
d2
d1
d0
-
-
1
1
1
1
1
0
Only for testing
IFSEXP
-
0
-
-
-
-
-
-
1
Enable expand mode of IF sampling time (see addr 4)
Disable expand mode of IF sampling time
EWEXP
0
1
-
-
-
-
-
-
-
Enable expand mode of error window (see addr 4)
Disable expand mode of error window
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Appendix
6
TDA7541B
Appendix
Figure 8.
68/77
Block diagram FM part
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TDA7541B
Appendix
Figure 9.
Block diagram VCO
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Appendix
TDA7541B
Figure 10. Block diagram ISS function
70/77
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TDA7541B
Appendix
Figure 11. Block diagram AM path
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Appendix
TDA7541B
Figure 12. Block diagram stereo decoder
MPXOUT
MPXIN
L
R
MUX
MPTC FSTC
Figure 13. Block diagram audio noise blanker
MPXIN
Stereo
decoder
L/R
NBENA
Monoflop
FM:22-40µs
AM:0.3-1.2ms
NBT
S&H
FMON
VTH
Deviation
detector
140kHz HPF
(2nd. order)
Rectifier
Integrator
discharge control
NBPC
NBMP
NBSMP NBRR
MPTC
72/77
Threshold
generator
NBCT
NBDC
FMDEMOut
PEAK
RECT
FMON
Doc ID 16048 Rev 1
NBLT
Fieldstrenght
adjust
NBFC
FSTC
TDA7541B
Appendix
Figure 14. Block diagram multi path detection for stereo decoder
Stereo
blend
FSTC
Attack/Decay
MUX
MPINT
Rectifier
MPCC
FS
Bandpass
19kHz
internal
MPFAST/
SEEK
Rectifier
MPG
MPRG
MPTC
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AC00706
FM_AM
8.5V
22n
8.5V
10
330n
100n
16
15
14
1µ
13
12
11
10
9
8
7
6
5
4
3
2
1
10
8.5V
100n
330p
VCCVCO
VCOE
VCOB
FMAGCTC
FMPINDR
TV
FMMIX1IN2
GNDRF
FMMIX1IN1
AMPINDR
AMMI X1REF
WB
AMRFAGCOUT
AMMI X1IN
DEVTC
VCCMIX1
220n
64
MIX1OUT
GNDVCO
17
680 nH
62
MIX1REF
LPOUT
18
61
IF1AMPIN
63
GNDIF
19
LPF
20
VREF2
1µ
4.7
60
100n
1µ
100n
2.2µ
100n
100n
1
X1
450kHz
CF3
51
52
180p
AMI F2IN
49
GNDVCC1
L
R
VCC1
FSWO
GNDSTD
MPTC
AMREFDEMC
MPXI N
MUTETC
MPXOUT
AM IF2REF
FMREFDEMC
GNDDEM
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
22µ
4.7
8.5V
VREF1
100n
Q_Loaded 28
L=560nH
TDA7541B
SW
22
8.5V
23
MUX
MUX
SSTOP
24
SSTOP
VCCIF1
0.7MHz
CF2
26
SDA
25
SDA
SCL
SCL
FSU
27
FSU
LPHC
21
59
IF1AMPOUT
58
IF1REF
57
AMA GC2TC
56
MIX2IN
55
MI X2INREF
54
AMRFAGCTC
53
MIX2OUT
28
FSTC
100n
MIX2REF
XTALG
29
VCC2
30
50
MIX2AMPOUT
31
GNDVCC2
32
ISSTC2
3.3n
ISSTC1
330n
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1µ
100n
470n
100n
470n
2.2µ
470n
L
100n
470n
22
AM _AF/MPX
8.5V
7
R
10.7MHz
CF1
Application circuit
TDA7541B
Application circuit
Figure 15. Application circuit
100p
TDA7541B
Package information
In order to meet environmental requirements, ST offers these devices in different grades of
ECOPACK® packages, depending on their level of environmental compliance. ECOPACK®
specifications, grade definitions and product status are available at: www.st.com.
ECOPACK® is an ST trademark.
Figure 16. LQFP64 mechanical data and package dimensions
mm
inch
DIM.
MIN.
TYP.
MAX.
A
MIN.
TYP.
1.60
0.063
A1
0.05
0.15
0.002
A2
1.35
1.40
1.45
0.053
0.006
0.22
0.27
0.0066 0.0086 0.0106
0.20
0.0035
0.055
0.057
B
0.17
C
0.09
D
11.80
12.00
12.20
0.464
0.472
0.480
D1
9.80
10.00
10.20
0.386
0.394
0.401
0.0079
D3
7.50
0.295
e
0.50
0.0197
E
11.80
12.00
12.20
0.464
0.472
0.480
E1
9.80
10.00
10.20
0.386
0.394
0.401
0.45
0.60
0.75
0.0177 0.0236 0.0295
E3
7.50
L
OUTLINE AND
MECHANICAL DATA
MAX.
0.295
L1
1.00
K
0˚ (min.), 3.5˚ (min.), 7˚(max.)
0.0393
ccc
0.080
LQFP64 (10 x 10 x 1.4mm)
0.0031
D
D1
A
D3
A2
A1
48
33
49
32
0.08mm ccc
B
Seating Plane
E
E1
E3
B
17
64
1
16
C
e
L
L1
8
Package information
K
TQFP64
0051434 F
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Revision history
9
TDA7541B
Revision history
Table 43.
76/77
Document revision history
Date
Revision
22-Jul-2009
1
Changes
Initial release.
Doc ID 16048 Rev 1
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