TDA7405
EQUALIZER CARRADIO SIGNAL PROCESSOR
1
FEA TURES 3 STEREO INPUTS 3 MONO INPUTS DYNAMIC-COMPRESSION-STAGE FOR CD BASS, TREBLE AND LOUDNESS CONTROL EQ-FILTERS FOR SEPARATE FRONT/REAREQUALIZATION VOICE-BAND-FILTER FOR MIXING-CHANNEL DIRECT MUTE AND SOFTMUTE INTERNAL BEEP FOUR INDEPENDENT SPEAKER-OUTPUTS INDEPENDENT SECOND SOURCE-SELECTOR FULL MIXING CAPABILITY PAU SE DETECTOR
Figure 1. Package
TQFP44
Table 1. Order Codes
Part Number TDA7405 Package TQFP44
1.2 Digital control:
I2C-BUS INTERFACE DESCRIPTION
1.1 Stereodecoder RDS MUTE NO EXTERNAL ADJUSTMENTS AM/FM NOISEBLANKER WITH SEVERAL TRIGGER CONTROLS PROG RAM M ABL E MULTIPATH DETECTOR QUALITY DETECTOR OUTPUT
2
The device includes a high performance audioprocessor and a stereodecoder-noiseblanker combination with the whole low frequency signal processing necessary for state-of-the-art as well as future carradios. The digital control allows a programming in a wide range of all the filter characteristics. Also the stereodecoder part offers several possibilities of programming especially for the adaptation to different IF-devices.
Figure 2. BLOCK DIAGRAM
May 2004
REV. 2 1/57
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Table 2. SUPPLY
Symbol Vs Is SVRR Parameter Supply Voltage Supply Current Ripple Rejection @ 1KHz Vs = 9V Audioprocessor(all Filters flat) Stereodecoder + Audioprocessor Test Condition Min. 7.5 45 Typ. 9 65 60 55 Max. 10.5 85 Unit V mA dB dB
Table 3. THERMAL DATA
Symbol Parameter Value 65 Unit C/W
RTh j-pins Thermal Resistance Junction-pins max
Table 4. ABSOLUTE MAXIMUM RATINGS
Symbol Vs Tamb Tstg Operating Supply Voltage Operating Temperature Range Storage Temperature Range Parameter Value 10.5 -40 to 85 -55 to +150 Unit V C C
3 ESD All pins are protected against ESD according to the MIL883 standard. Figure 3. PIN CONNECTION (Top view)
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Figure 4. BLOCK DIAGRAM (Enlarged view)
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4 AUDIOPROCESSOR PART 2 fully differential CD stereo inputs with programmable attenuation 1 single-ended stereo input 2 differential mono input 1 single-ended mono input In-Gain 0..15dB, 1dB steps internal Offset-cancellation (AutoZero) separate second source-selector Beep Mixing stage Loudness internal Beep with 3 frequencies + diagnostic setting (19kHz tone) Beep, Phone,Navigation and FM mixable to all speaker-outputs (see Figure 20) programmabe Voice-Band Filter programmable center frequency and frequency response 15 x 1dB steps selectable flat-mode (constant attenuation) Volume 0.5dB attenuator 100dB range soft-step control with programmable times Bass 2nd order frequency response center frequency programmable in 8 steps DC gain programmable 15 x 0.5dB steps Treble 2nd order frequency response center frequency programmable in 4 steps 15 x 1dB steps Equalizer two stereo equalizing-filters for separate front/rear adaption 1st filter center-frequency programmable in 16 steps (4 steps/octave, min 63Hz, max 840Hz) 2nd filter center-frequency programmable in 16 steps (4 steps/octave, min 300Hz, max 4kHz) quality factor programmable in 4 steps 15 x 1dB steps selectable flat-mode Speaker 4 independent speaker controls in 1dB steps control range 95dB separate Mute Mute Functions Pause Detector Compander direct mute digitally controlled SoftMute with 4 programmable mute-times programmable threshold dynamic range compression for use with CD 2:1 compression rate programmable max. gain
Features: Input Multiplexer
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Table 5. ELECTRICAL CHARACTERISTICS (VS=9V; Tamb=25C; RL=10k; all gains=0dB; f=1kHz; unless otherwise specified)
Symbol INPUT SELECTOR Ri n VCL SIN GIN MIN GIN MAX GSTEP V DC Input Resistance Clipping Level Input Separation Min. Input Gain Max. Input Gain Step Resolution DC Steps Adjacent Gain Steps GMIN to GMAX Voffset Remaining offset with AutoZero all single ended Inputs 70 2.0 80 -1 13 0.5 -5 -10 100 2.2 100 0 15 1 1 1 0.5 +1 17 1.5 5 10 130 k VRMS dB dB dB dB mV mV mV Parameter Test Condition Min. Typ. Max. Unit
DIFFERENTIAL STEREO INPUTS Ri n G CD Input Resistance (see Fig. 1) Gain Differential only at true differential input 70 -1 -5 -11 CMRR Common Mode Rejection Ratio VCM = 1VRMS @ 1kHz VCM = 1VRMS @ 10kHz e NO Output-Noise @ Speaker-Outputs 20Hz - 20kHz, flat; all stages 0dB 46 46 100 0 -6 - 12 70 60 9 15 130 1 -7 -1 3 k dB dB dB dB dB V
DIFFERENTIAL MONO INPUTS Ri n CMRR Input Impedance Common Mode Rejection Ratio Differential VCM = 1VRMS @ 1kHz VCM = 1VRMS @ 10kHz BEEP CONTROL VRMS fBeep Beep Level Beep Frequency Mix-Gain = 6dB fBeep1 fBeep2 fBeep3 fBeep4
1. The Level for the 19kHz-Testtone is 2.1VRMS
40 46 46
56 70 60
72
k dB dB
250 470 740 1.7 18
3501) 500 780 1.8 19
500 530 820 1.9 20
mV Hz Hz kHz kHz
MIXING CONTROL MLEVEL GMAX AMAX ASTEP Mixing Ratio Max. Gain Max. Attenuation Attennuation Step Main / Mix-Source 13 -83 0.5 -6/-6 15 -79 1 17 -7 5 1.5 dB dB dB dB
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Table 5. ELECTRICAL CHARACTERISTICS (continued) (VS=9V; Tamb=25C; RL=10k; all gains=0dB; f=1kHz; unless otherwise specified)
Symbol MULTIPLEXER ROUT RL CL V DC DC Voltage Level 4.3 4.5 Parameter OUTPUT2) 800 2 10 4.7 1000 k nF V Test Condition Min. Typ. Max. Unit
Output Impedance Output Load Capacitance
2. If confgured as Multiplexer-Output
LOUDNESS CONTROL ASTEP AMAX fPeak Step Resolution Max. Attenuation Peak Frequency f P1 f P2 f P3 f P4 VOLUME CONTROL GMAX AMAX ASTEP EA Max. Gain Max. Attenuation Step Resolution Attenuation Set Error G = -20 to +20dB G = -80 to -20dB ET V DC Tracking Error DC Steps Adjacent Attenuation Steps From 0dB to GMIN SOFT MUTE AMUTE TD Mute Attenuation Delay Time T1 T2 T3 T4 VTH low VTH high RP U VPU Low Threshold for SM-Pin3) High Threshold for SM - Pin Internal pull-up resistor Internal pull-up Voltage 2.5 32 45 3.3 58 70 200 80 100 0.48 0.96 123 324 1 2 170 600 1 dB ms ms ms ms V V k V 0.1 0.5 30 -83 0 -0.75 -4 32 -79.5 0.5 0 0 34 -7 5 1 +0.75 3 2 3 5 dB dB dB dB dB dB mV mV 0.5 -21 180 360 540 720 1 -19 200 400 600 800 1.5 -1 7 220 440 660 880 dB dB Hz Hz Hz Hz
3. The SM-Pin is active low (Mute = 0)
BASS CONTROL CRANGE ASTEP Control Range Step Resolution 14 0.1 +15.5 0.5 16 1.0 dB dB
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Table 5. ELECTRICAL CHARACTERISTICS (continued) (VS=9V; Tamb=25C; RL=10k; all gains=0dB; f=1kHz; unless otherwise specified)
Symbol fC Parameter Center Frequency f C1 f C2 f C3 f C4 f C5 f C6 f C7 f C8 QBASS Quality Factor Q1 Q2 Q3 Q4 DCGAIN Bass-DC-Gain DC = off DC = on TREBLE CONTROL CRANGE ASTEP fC Control Range Step Resolution Center Frequency f C1 f C2 f C3 f C4 PAUSE DETECTOR4) VTH Zero Crossing Threshold Window 1 Window 2 Window 3 IDELAY VTHP Pull-Up Current Pause Threshold 15 40 80 160 25 3.0 35 mV mV mV A V 14 0.5 8 10 12 14 +15 1 10 12.5 15 17.5 16 1.5 12 15 18 21 dB dB kHz kH z kHz kH z Test Condition Min. 54 63 72 81 90 117 135 180 0.9 1.1 1.3 1.8 -1 4 Typ. 60 70 80 90 100 130 150 200 1 1.25 1.5 2 0 4.4 Max. 66 77 88 99 110 143 165 220 1.1 1.4 1.7 2.2 +1 6 dB dB Unit Hz Hz Hz Hz Hz Hz Hz Hz
4. If configured as Pause-Output
SPEAKER ATTENUATORS Ri n GMAX AMAX ASTEP AMUTE Input Impedance Max. Gain Max. Attenuation Step Resolution Output Mute Attenuation 35 14 -83 0.5 80 50 15 -79 1 90 65 16 -7 5 1.5 k dB dB dB dB
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Table 5. ELECTRICAL CHARACTERISTICS (continued) (VS=9V; Tamb=25C; RL=10k; all gains=0dB; f=1kHz; unless otherwise specified)
Symbol EE V DC Parameter Attenuation Set Error DC Steps Adjacent Attenuation Steps 0.1 Test Condition Min. Typ. Max. 2 5 Unit dB mV
MONO VOICE BANDPASS fHP Highpass corner frequency f HP 1 f HP 2 f HP 3 f HP 4 f HP 5 f HP 6 f HP 7 f HP 8 fLP Lowpass corner frequency fLP1 fLP2 COMPANDER GMAX max. Compander Gain Vi < -46dB Vi < -46dB, Anti-Clip=On tAtt Attack time tAtt1 tAtt2 tAtt3 tAtt4 tRel Release time tRel1 tRel2 tRel3 tRel4 VREF Compander Reference InputLevel (equals 0dB) VREF1 VREF2 VREF3 CF Compression Factor Output Signal / Input Signal 19 29 6 12 24 49 390 780 1.17 1.56 0.5 1.0 2.0 0.5 dB dB ms ms ms ms ms ms s s VRMS VRMS VRMS 81 120 162 193 270 405 540 675 2.7 5.4 90 135 180 215 300 450 600 750 3 6 99 150 198 237 330 495 660 825 3.3 6.6 Hz Hz Hz Hz Hz Hz Hz Hz kHz kHz
AUDIO OUTPUTS VCLIP RL CL ROUT V DC Clipping Level Output Load Resistance Output Load Capacitance Output Impedance DC Voltage Level 4.3 30 4.5 d = 0.3% 2.0 2 10 120 4.7 2.2 VRMS k nF V
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Table 5. ELECTRICAL CHARACTERISTICS (continued) (VS=9V; Tamb=25C; RL=10k; all gains=0dB; f=1kHz; unless otherwise specified)
Symbol GENERAL e NO Output Noise BW = 20Hz - 20kHz;output muted BW = 20Hz - 20kHz all gains = 0dB single ended inputs S/N Signal to Noise Ratio all gains = 0dB flat; VO = 2VRMS bass, treble at +12dB; a-weighted; VO = 2.6VRMS d distortion VIN = 1VRMS ; all stages 0dB VOUT = 1VRMS ; Bass & Treble = 12dB SC ET Channel Separation left/right Total Tracking Error AV = 0 to -20dB AV = -20 to -60dB 80 -1 -2 3 10 106 100 0.005 0.05 100 0 0 1 2 0.1 0.1 15 20 V V dB dB % % dB dB dB Parameter Test Condition Min. Typ. Max. Unit
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5 DESCRIPTION OF THE AUDIOPROCESSOR PART
5.1 Input stages In the basic configuration two full-differential, two mono-differential, one single ended stereo and one singleended mono input are available. In addition a dedicated input for the stereodecoder MPX-signal is present. Figure 5. Input stages
5.1.1 Full-differential stereo Input 1 (FD1) The FD1-input is implemented as a buffered full-differential stereo stage with 100k input-impedance at each input. The attenuation is programmable in 3 steps from 0 to -12dB in order to adapt the incoming signal level. A 6dB attenuation is included in the differential stage, the additional 6dB are done by a following resistive divider. This input is also configurable as two single-ended stereo inputs (see pin-out). 5.1.2 Full-differential stereo Input 2 (FD2) The FD2-input has the same general structure as FD1, but with a programmable attenuation of 0 or 6dB embedded in the differential stage.
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5.1.3 Mono-differential Input 1 (MD1) The MD1-input is designed as a basic differential stage with 56k input-impedance. This input is configurable as a single-ended stereo input (see pin-out). 5.1.4 Mono-differential Input 2 (MD2) The MD2-input has the same topology as MD1, but without the possibility to configure it to single ended. 5.1.5 Single-ended stereo Input (SE1), single-ended mono input (AM) and FM-MPX input All single ended inputs offer an input impedance of 100kW. The AM-pin can be connected by software to the input of the stereodecoder in order to use the AM-Noiseblanker and AM-High-Cut feature. 5.2 AutoZero The AutoZero allows a reduction of the number of pins as well as external components by canceling any offset generated by or before the In-Gain-stage (Please notice that externally generated offsets, e.g. generated through the leakage current of the coupling capacitors, are not canceled). The auto-zeroing is started every time the DATA-BYTE 0 is selected and needs max. 0.3ms for the alignment. To avoid audible clicks the Audioprocessor is muted before the loudness stage during this time. The AutoZerofeature is only present in the main signal-path. 5.2.1 AutoZero for Stereodecoder-Selection A special procedure is recommended for selecting the stereodecoder at the main input-selector to guarantee an optimum offset-cancellation: (Step 0: SoftMute or Mute the signal-path) Step 1: Temporary deselect the stereodecoder at all input-selectors Step 2: Configure the stereodecoder via IIC-Bus Step 3: Wait 1ms Step 4: Select the stereodecoder at the main input-selector first The root cause of this procedure is, that after muting the stereodecoder (Step 1), the internal stereodecoder filters have to settle in order to perform a proper offset-cancellation. 5.2.2 AutoZero-Remain In some cases, for example if the P is executing a refresh cycle of the IIC-Bus-programming, it is not useful to start a new AutoZero-action because no new source is selected and an undesired mute would appear at the outputs. For such applications the A631 could be switched in the AutoZero-Remain-Mode (Bit 6 of the subaddress-byte). If this bit is set to high, the DATABYTE 0 could be loaded without invoking the AutoZero and the old adjustment-value remains. 5.3 Pause Detector / MUX-Output The pin number 40(Pause/MUX) is configurable for two different functions: 1. During Pause-Detector OFF this pin is used as a mono-output of the main input-selector. This signal is often used to drive a level-/equalizer-display on the carradio front-panel. 2. During Pause-Detector ON the pin is used to define the time-constant of the detector by an external capacitor. The pause-detector is driven by the internal stereodecoder-outputs in order to use pauses in the FM-signal for alternate-frequency-jumps. If the signal-level of both stereodecoder channels is outside the programmed voltage-window, the external capacitor is abruptly discharged. Inside the pause-condition the capacitor is slowly recharged by a constant current of 25A. The pause information is also available via IIC-Bus (see IIC-Bus programming).
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5.4 Loudness There are four parameters programmable in the loudness stage: 5.4.1 Attenuation Figure 6 shows the attenuation as a function of frequency at fP = 400Hz. Figure 6. Loudness Attenuation @ fP = 400Hz
0. 0
-5.0
-10.0
dB
-15.0
-20.0
-25.0 10.0
100.0
1.0K
10.0K
Hz
5.4.2 Peak Frequency Figure 7 shows the four possible peak-frequencies at 200, 400, 600 and 800Hz Figure 7. Loudness Center frequencies @ Attn. = 15dB
0.0
-5.0
dB
-10.0
-15.0
-20.0 10.0
100.0
1.0K
10.0K
Hz
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5.4.3 Loudness Order Different shapes of 1st and 2nd-Order Loudness Figure 8. 1st and 2nd Order Loudness @ Attn. = 15dB, fP=400Hz
0.0
-5.0
dB
-10.0
-15.0
-20.0 10.0
100.0
Hz
1.0K
10.0K
5.4.4 Flat Mode In flat mode the loudness stage works as a 0dB to -19dB attenuator. 5.5 SoftMute The digitally controlled SoftMute stage allows muting/demuting the signal with a I2C-bus programmable slope. The mute process can either be activated by the SoftMute pin or by the I2C-bus. This slope is realized in a special S-shaped curve to mute slow in the critical regions (see Figure 9). For timing purposes the Bit of the I2Cbus output register is set to 1 from the start of muting until the end of de-muting. Figure 9. Softmute-Timing
Note: Please notice that a started Mute-action is always terminated and could not be interrupted by a change of the mute -signal.
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5.6 SoftStep-Volume When the volume-level is changed audible clicks could appear at the output. The root cause of those clicks could either be a DC-Offset before the volume-stage or the sudden change of the envelope of the audiosignal. With the SoftStep-feature both kinds of clicks could be reduced to a minimum and are no more audible. The blend-time from one step to the next is programmable in four steps. Figure 10. SoftStep-Timing
1dB
0.5dB
SS Time -0.5dB
-1dB
Note: For steps more than 0.5dB the SoftStep mode should be deactivated because it could generate a hard 1dB step during the blend-time
5.7 Bass There are four parameters programmable in the bass stage: 5.7.1 Attenuation Figure 11 shows the attenuation as a function of frequency at a center frequency of 80Hz. Figure 11. Bass Control @ fC = 80Hz, Q = 1
1 5.0
1 0.0
5.0
dB
0.0
-5.0
-10 .0
-15 .0 10 .0 100. 0
Hz
1 .0K
10.0K
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5.7.2 Center Frequency Figure 12 shows the eight possible center frequencies 60, 70, 80, 90, 100, 130, 150 and 200Hz. Figure 12. Bass center Frequencies @ Gain = 14dB, Q = 1
15.0
12.5
10.0
7.5
dB
5.0
2.5
0.0 10.0 100.0 1.0K 10.0K
Hz
5.7.3 Quality Factors Figure 13 shows the four possible quality factors 1, 1.25, 1.5 and 2. Figure 13. Bass Quality factors @ Gain = 14dB, fC = 80Hz
15.0
12.5
10.0
7.5
5.0
2.5
0.0
10.0
100.0
1. 0K
10.0K
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5.7.4 DC Mode In this mode the DC-gain is increased by 4.4dB. In addition the programmed center frequency and quality factor is decreased by 25% which can be used to reach alternative center frequencies or quality factors. Figure 14. Bass normal and DC Mode @ Gain = 14dB, fC = 80Hz
1 5 .0
1 2 .5
1 0 .0
7 .5
5 .0
2 .5
0.0 10. 0 100.0 1.0K 10.0K
Note: The center frequency, Q and DC-mode can be set fully independently.
5.8 Treble There are two parameters programmable in the treble stage: 5.8.1 Attenuation Figure 15 shows the attenuation as a function of frequency at a center frequency of 17.5kHz. Figure 15. Treble Control @ fC = 17.5kHz
15.0
10.0
5.0
0.0
-5.0
-10.0
-15.0 10.0 100.0 1.0K 10.0K
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5.8.2 Center Frequency Figure 16 shows the four possible center frequencies 10k, 12.5k, 15k and 17.5kHz. Figure 16. Treble Center Frequencies @ Gain = 14dB
15.0
12.5
10.0
7 .5
5 .0
2 .5
0.0
10.0
100.0
1.0K
10.0K
5.9 EQ-Filter There are two EQ-Filters present in the A631: one for the High-Frequency-Range and one for the Low-Frequency-Range with a certain overlap. They are programmable in center-frequeny (4 frequencies/octave), in Q(4 settings) and in Attenuation (1dB-steps). In addition several configurations are possible to use the filters in the frontor rear-path. Table 6. Gain, Center Frequency and Quality Factor of Equalizer Filters
Parameter Gain Center Frequency Filter 1 Center Frequency Filter 2 Quality Factor Min -15 63 300 1 Max 15 840 4000 4 Unit dB Hz Hz
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5.9.1 Equalizer-Setup The two Filters can be configured in multiple ways in order to cover as most as possible applications. Both filters can be programmed to be either in the front- or in the rear-path, respectively. This feature enables to have e.g. the High-Filter in the front- and both filters in the rear-path. Figure 17. Equalizer Configuration
5.9.2 Attenuation Figure 18 shows the attenuation as a function of frequency at a center frequency of 625 Hz. Figure 18. Gain/Attenuation of EQ-Filter
15 dB 10
5
0
-5
-10
-15 2e+01 1e+02 1e+03 1e+04 Hz 2e+0 4
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5.9.3 Frequencies Figure 19 shows the different center frequencies of the EQ-Filter at 12 dB gain Figure 19. Center-Frequencies of EQ-Filter
14 dB 12
10
8
6
4
2
0
-2 2e+01 1e+02 1e+03 1e +04 Hz 2e+0 4
5.9.4 Q-Factor Figure 20 shows the four possible quality factors 1, 2, 3 and 4. Figure 20. Different Q-factors of Equalizer-Filter
14 dB 12
10
8
6
4
2
0
-2 2e+01
1e+02
1 e+03
1e+04 Hz
2 e+04
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5.10 Compander 5.10.1 Signal-Compression A fully integrated signal-compressor with programmable Attack- and Decay-times is present in the A631 (see Figure 20). The compander consists of a signal-level detection, an A/D-Converter plus adder and the normal SoftStep-Volume-stage. First of all the left and the right InGain-signal is rectified, respectively, and the logarithm is build from the summed signal. The following low-pass smooth the output-signal of the logarithm-amplifier and improves the low-frequency suppression. The low-pass output-voltage then is A/D-converted an added to the current volume-word defined by the IIC-Bus. Assuming reference-level or higher at the compander input, the output of the ADC is 0. At lower levels the voltage is increasing with 1 Bit/dB. It is obvious that with this configuration and a 0.5dB-step volume-stage the compression rate is fixed to 2:1 (1dB less at the input leads to 0.5dB less at the output). The internal reference-level of the compander is programmable in three steps from 0.5VRMS to 2VRMS. For a proper behavior of the compression-circuit it is mandatory to have at a 0dB input-signal exactly the programmed reference-level after the InGain-stage. E.g. at a configured reference-level of 0.5VRMS the output of the InGain-stage has to have also 0.5VRMS at 0dB source-signal (Usually the 0dB for CD is defined as the maximum possible signal-level). To adapt the external level to the internal reference-level the programmable attenuation in the differential-stages and the InGain can be used. Figure 21. Compander Block Diagram
5.10.2 Anti-Clipping In a second application the compander-circuit can be used for a Anti-Clipping or Limiting function. In this case one of the dedicated inputs (AM or MPin) is connected directly to the Clip-Detector of the Power-Amplifier. If no clipping is detected, the open-collector output of the Power-Amplifier is highohmic and the input-voltage of the rectifier is VREF. The level-detector interprets this as a very small signal and reacts with the maximum programmed compander-gain. In the application this gain has to be compensated by decreasing the volume with the same value in order to get the desired output-level. In clipping situation the open-collector-current generates a voltage-drop at the rectifier-input, which forces the compander to decrease the gain until the clipping disappears. It is even possible to run the compression-mode and the Anti-Clipping mode in parallel. In this case the maximum compander-Gain should be set to 29 dB.
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5.10.3 Characteristic To achieve the desired compression characteristic like shown below the volume has to be decreased by 4dB. Figure 22. Compander Characteristic
0 -8dB -10
Output Level
-20
2:1
dB
-30
-38dB
15dB -40
-50
-60 0 -10 - 20 -30 -40 -50 -60
Input Level
dB
5.10.4 I²C -BUS-Timing When the Compander is active a volume- word coming from this stage is added to the I2C-Bus volume-word and the volume is changed with a soft slope between adjacent steps (SoftStep-stage). As mentioned in the description of this stage it is not recommended to change the volume during this slope. To avoid this behaviourwhile the Compander is working, and the volume has to be changed, the compander-hold-bit is implemented (Bit 7 in the subaddress-byte). The recommended timing for changing the volume during compander-ON is the following: 1. Set the compander-hold-bit 2. Wait the actual SoftStep-time 3. Change the volume 4. Reset the compander-hold-bit The SoftStep-times are in compander-ON condition automatically adapted to the attack-time of the Compander. In the following table the related SoftStep-times are shown:
Attack-Time 6 ms 12ms 24ms 48ms SoftStep-Time 0.16ms 0.32ms 0.64ms 1.28ms
5.10.5 AC-Coupling In some applications additional signal manipulations are desired, for example surround-sound or more-bandequalizing. For this purpose an AC-Coupling is placed before the speaker-attenuators, which can be activated or internally shorted by I²C-Bus. In short condition the input-signal of the speaker-attenuator is available at the AC-Outputs. The input-impedance of this AC-Inputs is 50k.
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5.10.6 Output Selector The output-selector allows to connect the main- or the second-source to the Front-, Rear-speaker-attenuator, respectively. As an example of this programming the device is able to connect via software the main-source to the back (rear) and the second-source to the front (see Figure 23). Figure 23. Output Selector
5.10.7 Speaker-Attenuator and Mixing A Mixing-stage is placed after each speaker-attenuator and can be set independently to mixing-mode. Having a full volume for the Mix-signal the stage offers a wide flexibility to adapt the mixing levels. Figure 24. Mixing Configuration
5.10.8 Audioprocessor Testing During the Testmode, which can be activated by setting bit D0 of the stereodecoder testing-byte and the audioprocessor testing byte, several internal signals are available at the FD2R- pin. During this mode the input resistance of 100kOhm is disconnected from the pin. The internal signals available are shown in the Data-byte specification.
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6 STEREOD ECODER-PART
6.1 Features:
no external components necessary PLL with adjustment free, fully integrated VCO automatic pilot dependent MONO/STEREO switching very high suppression of intermodulation and interference programmable Roll-Off compensation dedicated RDS-Softmute Highcut- and Stereoblend-characterisctics programmable in a wide range FM/AMNoiseblanker with several threshold controls Multipath-detector with programmable internal/external influence I2C-bus control of all necessary functions
Table 7. ELECTRICAL CHARACTERISTICS VS = 9V, deemphasis time constant = 50s, MPX input voltage VMPX = 500mV (75kHz deviation), modulation frequency = 1kHz, input gain = 6dB, Tamb = 27C, unless otherwise specified.
Symbol Vin Ri n Gmin Gmax Gstep SVRR THD S+N -------------N Parameter MPX Input Level Input Resistance Min. Input Gain Max. Input Gain Step Resolution Supply Voltage Ripple Rejection Max. Channel Separation Total Harmonic Distortion Signal plus Noise to Noise Ratio fin=1kHz, mono A-weighted, S = 2Vrms 80 Vripple = 100mV, f = 1kHz 30 Test Conditions Input Gain = 3.5dB 70 1.5 8.5 1.75 Min. Typ. 0.5 100 3.5 11 2.5 55 50 0.02 91 0.3 Max. 1.25 130 4.5 12.5 3.25 Unit Vrms k dB dB dB dB dB % dB
MONO/STEREO-SWITCH VPTHST1 VPTHST0 Pilot Threshold Voltage Pilot Threshold Voltage for Stereo, PTH = 1 for Stereo, PTH = 0 for Mono, PTH = 1 for Mono, PTH = 0 10 15 7 10 15 25 12 19 25 35 17 25 mV mV mV mV
VPTHMO1 Pilot Threshold Voltage VPTHMO0 Pilot Threshold Voltage P LL f/f Capture Range
0.5
%
DEEMPHASIS and HIGHCUT
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Table 7. ELECTRICAL CHARACTERISTICS (continued) VS = 9V, deemphasis time constant = 50s, MPX input voltage VMPX = 500mV (75kHz deviation), modulation frequency = 1kHz, input gain = 6dB, Tamb = 27C, unless otherwise specified.
Symbol DeempF
M
Parameter Deemphasis Timeconstants FM
Test Conditions VLEVEL >> VHCH VLEVEL >> VHCH VLEVEL >> VHCH VLEVEL >> VHCH
Min. 25 44 50 70
Typ. 50 62.5 75 100 3 37.5 47 56 75 3.7
Max. 75 80 100 130
Unit s s s s
MFM DeempA
M
Highcut Timeconstant Multiplier FM VLEVEL << VHCL Deemphasis Timeconstants AM VLEVEL >> VHCH VLEVEL >> VHCH VLEVEL >> VHCH VLEVEL >> VHCH
s s s s
MAM REF5V Lmin Lmaxs LGstep
Highcut Timeconstant Multiplier AM Internal Reference Voltage min. LEVEL Gain max. LEVEL Gain LEVEL Gain Step Resolution
VLEVEL << VHCL 4.7 -1 5 see section 2.7 see section 2.8 see section 2.8 see section 2.8 see section 2.9 see section 2.9 see section 2.9 see section 2.9 see section 2.9 see section 2.9 0.2 17 62 1.6 37 58 4.2 15 29 2.1
5 0 6 0.4 20 70 3.3 42 66 8.4 17 33 4.2
5.3 1 7 0.6 23 78 5.0 47 74 12.6 19 37 6.3
V dB dB dB %REF5V %REF5V %REF5V %REF5V %REF5V %REF5V %VHCH %VHCH %REF5V
VSBLmin Min. Voltage for Mono VSBLmax Max. Voltage for Mono VSBLstep Step Resolution VHCHmin Min. Voltage for NO Highcut VHCHmax Max. Voltage for NO Highcut VHCHstep Step Resolution VHCLmin Min. Voltage for FULL High cut VHCLmax Max. Voltage for FULL High cut VHCLstep Step Resolution
Carrier and harmonic suppression at the output 19 38 57 76 Pilot Signalf=19kHz Subcarrier f=38kHz Subcarrier f=57kHz Subcarrier f=76kHz 40 50 75 62 90 dB dB dB dB
Intermodulation (Note 1)
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Table 7. ELECTRICAL CHARACTERISTICS (continued) VS = 9V, deemphasis time constant = 50s, MPX input voltage VMPX = 500mV (75kHz deviation), modulation frequency = 1kHz, input gain = 6dB, Tamb = 27C, unless otherwise specified.
Symbol 2 3 Parameter fmod=10kHz, fspur=1kHz fmod=13kHz, fspur=1kHz Test Conditions Min. Typ. 65 75 Max. Unit dB dB
Traffic Radio (Note 2) 57 Signal f=57kHz 70 dB
SCA - Subsidiary Communications Authorization (Note 3) 67 Signal f=67kHz 75 dB
ACI - Adjacent Channel Interference (Note 4) 114 190 Signal f=114kHz Signal f=190kHz 95 84 dB dB
7
NOTES TO THE CHARACTERISTICS Vo ( s i g n a l)( a t 1 k H z ) 2 = --------------------------------------------------------------- ; s = ( 2 10 k H z ) 19 k H z Vo ( s p u r i o u s ) ( a t 1 k H z ) Vo ( s i g n a l)( a t 1 k H z ) 3 = --------------------------------------------------------------- ; s = ( 3 13 k H z ) 38 k H z Vo ( s p u r i o u s ) ( a t 1 k H z )
Note 1. Intermodulation Suppression
measured with: 91% pilot signal; fm = 10 kHz or 13 kHz. Note 2. Traffic Radio (V.F.) Suppression measured with: 91% stereo signal; 9% pilot signal; fm=1kHz; 5% subcarrier (f=57kHz, fm=23Hz AM, m=60%) Vo ( s i g n a l ) ( a t 1 k H z ) 5 7 ( V .W .F. ) = -----------------------------------------------------------------------------------V o ( s p u r i o u s ) ( a t 1 k H z 23kHz )
Note 3. SCA ( Subsidiary Communications Authorization ) Vo ( s i g n a l) ( a t 1 k H z ) 67 = --------------------------------------------------------------- ; s = ( 3 38 k H z ) 67 k H z Vo ( s p u r io u s )( a t 9 k H z ) measured with: 81% mono signal; 9% pilot signal; fm=1kHz; 10%SCA - subcarrier ( fs = 67kHz, unmodulated ).
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Note 4. ACI ( Adjacent Channel Interference ) Vo ( s i g n a l ) ( a t 1 k H z ) 114 = --------------------------------------------------------------- ; s = 110 k H z ( 3 38 k H z ) Vo ( s p u r io u s )( a t 4 k H z) Vo ( s i g n a l ) ( a t 1 k H z ) 190 = --------------------------------------------------------------- ; s = 186 k H z ( 5 38 k H z ) Vo ( s p u r io u s )( a t 4 k H z) measured with: 90% mono signal; 9% pilot signal; fm=1kHz; 1% spurious signal (fs = 110kHz or 186kHz, unmodulated).
8
NOISE BLANKER PART
8.1 Features:
AM and FM mode internal 2nd order 140kHz high-pass filter for MPX path internal rectifier and filters for AM-IF path programmable trigger thresholds trigger threshold dependent on high frequency noise with programmable gain additional circuits for deviation- and fieldstrength-dependent trigger adjustment 4 selectable pulse suppression times for each mode programmable noise rectifier charge/discharge current
Table 8. ELECTRICAL CHARACTERISTICS All parameters mesured in FM mode if not otherwise specified.
Symbol VTR Parameter Trigger Threshold 5) Test conditions meas.with VPEAK=0.9V 111 110 101 100 011 010 001 000 VTRNOISE noise controlled Trigger Threshold meas.with VPEAK=1.5V 00 01 10 11 Min. Typ. 30 35 40 45 50 55 60 65 260 220 180 140 Max. Unit mVOP mVOP mVOP mVOP mVOP mVOP mVOP mVOP mVOP mVOP mVOP mVOP
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Table 8. ELECTRICAL CHARACTERISTICS (continued) All parameters mesured in FM mode if not otherwise specified.
Symbol VRECT Parameter Rectifier Voltage Test conditions VMPX=0mV VMPX=50mV, f=150kHz VMPX=200mV, f=150kHz VRECTDEV Deviation dependent Rectifier Voltage meas.with VMPX=500mV (75kHz dev.) 11 10 01 00 11 10 01 00 00 01 10 11 00 01 10 11 00 01 10 11 0 1 00 01 10 11 35 Signal AM-RECTIFIER in Testmode Min. 0.5 1.5 2 0.5 0.9 1.7 2.5 0.5 0.9 1.7 2.1 Typ. 0.9 1.7 2.5 0.9 (off) 1.2 2.0 2.8 0.9 (off) 1.4 1.9 2.4 38 25.5 32 22 1.2 800 1.0 640 0.3 0.8 1.3 2.0 10 20 0.3 0.5 0.7 0.9 50 6 20 2 Signal AM-RECTIFIER in Testmode 14 56 65 Max. 1.3 2.1 2.9 1.3 1.5 2.3 3.1 1.3 1.5 2.3 3.1 Unit V V V VOP VOP VOP VOP V V V V s s s s ms s ms s V/ms
VRECTFS
Fieldstrength controlled Rectifier Voltage
meas.with VMPX=0mV, VLEVEL<< VSBL (fully mono) Signal HOLDN in Testmode
TSFM
Suppression Pulse Duration FM
TSAM
Suppression Pulse Duration AM
Signal HOLDN in Testmode
VRECTADJ Noise rectifier discharge adjustment
Signal PEAK in Testmode
SRPEAK VADJMP
Noise rectifier charge Noise rectifier adjustment through Multipath AM IF Input resistance
Signal PEAK in Testmode Signal PEAK in Testmode
mV / s V/ms
RAMIF
kOhm dB dB dB kHz kHz
GAMIF,min min. gain AM IF GAMIF,max max. gain AM IF GAMIF,step step gain AM IF fAMIF,min min. fc AM IF
fAMIF,max max. fc AM IF
5. All thresholds are measured using a pulse with TR = 2 s, THIGH= 2 s and TF = 10 s. The repetition rate must not increase the PEAK voltage.
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Figure 25. Noiseblanker Test-Pulse
V
in
V op
DC
T ime TR T HIGH T F
Figure 26. Trigger Threshold vs. VPEAK
VTH
260mV (00) 220mV (01) 180mV (10) 140mV (11)
MIN. TRIG. THRESHOLD
NOISE CONTROLLED TRIG. THRESHOLD
65mV 8 STEPS 30mV
0.9V
1.5V
VPEAK [V]
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Figure 27.
VPEAK [V ]
OP
00 2.8 01 2.0 10 1.2 0.9 Detector off (11)
20
32.5
45
75
DEVIATION [KHz]
Figure 28. Fieldstrenth Controlled Trigger Adjustment
VPEAK
MONO
STEREO
3V
2.4V (00) 1.9V (01) 1.4V (10) N OIS E ATC_SB OFF (11) 0.9 V
n oi sy signal
good signal
E'
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9 MULTIPATH DETECTOR
9.1 Features:
internal 19kHz band-pass filter programmable band-pass- and rectifier-gain selectable internal influence on Stereoblend and/or Highcut
Table 9. ELECTRICAL CHARACTERISTICS
Symbol fCMP GBPMP Parameter Center frequency of MultipathBandpass Bandpass Gain Test Conditions stereodecoder locked on Pilottone G1 G2 G3 G4 GRECTMP Rectifier Gain G1 G2 G3 ICHMP IDISMP Rectifier Charge Current Rectifier Discharge Current Min. Typ. 19 6 12 16 18 7.6 4.6 0 0.25 0.5 4 Max. Unit kHz dB dB dB dB dB dB dB A mA
Quality Detector A Multipath Influence Factor 00 01 10 11 0.70 0.85 1.00 1.15
10
FUNCTIONAL DESCRIPTION OF STEREODECODER
Figure 29. Blockdiagram of the Stereodecoder
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The stereodecoder-part of the A631 (see Figure 28) contains all functions necessary to demodulate the MPXsignal like pilottone-dependent MONO/STEREO-switching as well as "stereoblend" and "highcut". Adaptations like programmable input gain, roll-off compensation, selectable deemphasis time constant and a programmable fieldstrength input allow to use different IF-devices. 10.1 Stereodecoder-Mute The A631 has a fast and easy to control RDS-Mute function which is a combination of the audioprocessor's SoftMute and the high-ohmic mute of the stereodecoder. If the stereodecoder is selected and a SoftMute command is sent (or activated through the SM-pin) the stereodecoder will be set automatically to the high-ohmic mute condition after the audio-signal has been softmuted. Hence a checking of alternate frequencies could be performed. Additionally the PLL can be set to "Hold"-mode, which disables the PLL input during the mute time. To release the system from the mute condition simply the unmute-command must be sent: the stereodecoder is unmuted immediately and the audioprocessor is softly unmuted. Figure 30 shows the output-signal VO as well as the internal stereodecoder mute signal. This influence of SoftMute on the stereodecoder mute can be switched off by setting bit 3 of the SoftMute byte to "0". A stereodecoder mute command (bit 0, stereodecoder byte set to "1") will set the stereodecoder in any case independently to the high-ohmic mute state. If any other source than the stereodecoder is selected the decoder remains muted and the MPX-pin is connected to Vref to avoid any discharge of the coupling capacitor through leakage currents. No further mute command should be applied. Figure 30. Signals during stereodecoder's SoftMute
Figure 31. Signal-Control via SoftMute-Pin
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10.2 InGain + Infilter The InGain stage allows to adjust the MPX-signal to a magnitude of about 1Vrms internally which is the recommended value. The 4.th order input filter has a corner frequency of 80kHz and is used to attenuate spikes and noise and acts as an anti-aliasing filter for the following switch capacitor filters. 10.3 Demodulator In the demodulator block the left and the right channel are separated from the MPX-signal. In this stage also the 19-kHz pilottone is cancelled. For reaching a high channel separation the A631 offers an I2C-bus programmable roll-off adjustment which is able to compensate the lowpass behavior of the tuner section. If the tuner's attenuation at 38kHz is in a range from 7.2% to 31.0% the A631 needs no external network in front of the MPX-pin. Within this range an adjustment to obtain at least 40 dB channel separation is possible. The bits for this adjustment are located together with the fieldstrength adjustment in one byte. This gives the possibility to perform an optimization step during the production of the carradio where the channel separation and the fieldstrength control are trimmed. The setup of the Stereoblend characteristics which is programmable in a wide range is described in 2.8. 10.4 Deemphasis and Highcut The deemphasis-lowpass allows to choose a time constant between 37.5 and 100s. The highcut control range will be 2 x tDeemp or 2.7 x tDeemp dependent on the selected time constant (see programming section). The bit D7 of the hightcut-byte will shift timeconstant and range. Inside the highcut control range (between VHCH and VHCL) the LEVEL signal is converted into a 5 bit word which controls the lowpass time constant between tDeemp...3 (3.7) x tDeemp. Thereby the resolution will remain always 5 bits independently of the absolute voltage range between the VHCH- and VHCL-values. In addition the maximum attenuation can be fixed between 2 and 10dB. The highcut function can be switched off by I2C-bus (bit D7, Highcut byte set to "0"). The setup of the highcut characteristics is described in 4.9. 10.5 PLL and Pilottone-Detector The PLL has the task to lock on the 19kHz pilottone during a stereo-transmission to allow a correct demodulation. The included pilottone-detector enables the demodulation if the pilottone reaches the selected pilottone threshold VPTHST. Two different thresholds are available. The detector output (signal STEREO, see Blockdiagram) can be checked by reading the status byte of the A631 via I2C-bus. During a Softmute the PLL can be set into "Hold"-mode which freezes the PLL's state (bit D4, Softmute byte). After releasing the Softmute the PLL will again follow the input signal only by correcting the phase error. 10.6 Fieldstrength Control The fieldstrength input is used to control the highcut- and the stereoblend-function. In addition the signal can be also used to control the noiseblanker thresholds and as input for the multipath detector. These additional functions are described in sections 3.3 and 4. 10.7 LEVEL-Input and -Gain To suppress undesired high frequency modulation on the highcut- and stereoblend-control signal the LEVEL signal is lowpass filtered firstly. The filter is a combination of a 1.st-order RC-lowpass at 53kHz (working as antialiasing filter) and a 1.st-order switched-capacitor-lowpass at 2.2kHz. The second stage is a programmable gain stage to adapt the LEVEL signal internally to different IF-devices (see Testmode section 5: LEVELHCC). The gain is widely programmable in 16 steps from 0dB to 6dB (step=0.4dB). These 4 bits are located together with the Roll-Off bits in the "Stereodecoder-Adjustment"-byte to simplify a possible adjustment during the production of the carradio. This signal controls directly the Highcut stage whereas the signal is filtered again (fc=100Hz) before the stereoblend stage (see Figure 25).
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10.8 Stereoblend Control The stereoblend control block converts the internal LEVEL-voltage (LEVELSB) into an 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 REF5V. The lower limit can be programmed between 20 and 70% of REF5V in 3.3% steps (see Figure 31, Figure 29). To adjust the external LEVEL-voltage to the internal range two values must be defined: the LEVEL gain LG and VSBL (see Figure 32). At the point of full channel separation the external level signal has to be amplified that internally it becomes equal to REF5V. The second point (e.g. 10dB channel sep.) is then adjusted with the VSBL voltage. Figure 32. Internal stereoblend characteristics
The gain can be programmed through 4 bits in the "Stereodecoder-Adjustment"-byte. All necessary internal reference voltages like REF5V are derived from a bandgap circuit. Therefore they have a temperature coefficient near zero. Figure 33. Relation between internal and external LEVEL-voltages for setup of Stereoblend
70 20
10.9 Highcut Control The highcut control setup is similar to the stereoblend control setup : the starting point VHCH can be set with 2 bits to be 42, 50, 58 or 66% of REF5V whereas the range can be set to be 17, 22, 28 or 33% of VHCH (see Figure 30).
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Figure 34. Highcut characteristics
11
FUNCTIONAL DESCRIPTION OF THE NOISEBLANKER
In the automotive environment the MPX-signal as well as the AM-signal is disturbed by spikes produced by the ignition and other radiating sources like the wiper-motor. The aim of the noiseblanker part is to cancel the audible influence of the spikes. Therefore the output of the stereodecoder is held at the actual voltage for a time between 22 and 38s in FM (370 and 645s in AM-mode). The blockdiagram of the noiseblanker is given in Figure 34. Figure 35. Block diagram of the noiseblanker
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 triggerstage a pulse former generates the "blanking"-pulse. 11.1 Trigger Path FM The incoming MPX signal is highpass-filtered, amplified and rectified. This second order highpass-filter has a corner-frequency of 140kHz. The rectified signal, RECT, is integrated (lowpass filtered) to generate a signal called PEAK. The DC-charge/discharge behaviour can be adjusted as well as the transient behaviour(MP-discharge control). Also noise with a frequency 140kHz increases the PEAK voltage. The PEAK voltage is fed to a threshold generator, which adds to the PEAK-voltage a DC-dependent threshold VTH. Both signals, RECT and PEAK+VTH are fed to a comparator which triggers a re-triggerable monoflop. The monoflop's output activates the sample-and-hold circuits in the signalpath for the selected duration 11.2 Noise Controlled Threshold Adjustment (NCT) There are mainly two independent possibilities for programming the trigger threshold: 1. the low threshold in 8 steps (bits D1 to D3 of the noiseblanker-byte I) 2. and the noise adjusted threshold in 4 steps (bits D4 and D5 of the noiseblanker-byte I, see Figure 22).
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The low threshold is active in combination with a good MPX signal without noise; the PEAK voltage is less than 1V. The sensitivity in this operation is high. If the MPX signal is noisy (low fieldstrength) the PEAK voltage increases due to the higher noise, which is also rectified. With increasing of the PEAK voltage the trigger threshold increases, too. This gain is programmable in 4 steps (see Figure 25). 11.3 Additional Threshold Control Mechanism 11.3.1 Automatic Threshold Control by the Stereoblend voltage Besides the noise controlled threshold adjustment there is an additional possibility for influencing the trigger threshold which depends on the stereoblend control. The point where the MPX signal starts to become noisy is fixed by the RF part. Therefore also the starting point of the normal noise-controlled trigger adjustment is fixed (Figure 27). In some cases the behavior of the noiseblanker can be improved by increasing the threshold even in a region of higher fieldstrength. Sometimes a wrong triggering occurs for the MPX signal often shows distortion in this range which can be avoided even if using a low threshold. Because of the overlap of this range and the range of the stereo/mono transition it can be controlled by stereoblend. This increase of the threshold is programmable in 3 steps or switched off. 11.3.2 Over Deviation Detector If the system is tuned to stations with a high deviation the noiseblanker can trigger on the higher frequencies of the modulation or distortion. To avoid this behavior, which causes audible noise in the output signal, the noiseblanker 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. Offset and gain of this circuit are programmable in 3 steps with the bits D6 and D7 of the noiseblanker-byte I (bit combination '00' turns off the detector, see Figure 26). 11.3.3Multipath-Level To react on high repetitive spikes caused by a Multipath-situation, the discharge-time of the PEAK voltage can be decreased depending on the voltage-level at pin MPout. The A631 offers a linear as well as a threshold driven control. The linear influence of the Multipath-Level on the PEAK-signal (D7 of Multipath-Control-Byte) gives a discharge slewrate of 1V/ms1 . The second possibility is to activate the threshold driven discharge which switches on the 18kOhm discharge if the Multipath-Level is below 2.5V (D7 of noiseblanker-byte II-byte).
1
The slewrate is measured with RDischarge = nfinite and VMPout = 2.5V
11.3.4 AM mode of the Noiseblanker The A631 noiseblanker is also suitable for AM noise canceling. The detector uses in AM mode the 450kHz unfiltered IF-output of the tuner for spike detection. A combination of programmable gain-stage and lowpass-filter forms an envelope detector which drives the noiseblanker's input via a 120 kHz 1.st order highpass. In order to blank the whole spike in AM mode the hold-times of the sample and hold circuit are much longer then in FM (640s to 1.2ms). All threshold controls can be used like in FM mode. 11.4 Functional Description of the Multipath-Detector Using the Multipath-Detector the audible effects of a multipath condition can be minimized. A multipath-condition is detected by rectifying the spectrum around 19kHz in the fieldstrength signal. An external capacitor is used to define the attack- and decay-times for the Stereoblend (see blockdiagram, Figure 35). Due to the very small charge currents this capacitor should be a low leakage current type (e.g. ceramic). Using this configuration an adaptation to the user's requirement is possible without effecting the "normal" fieldstrength input (LEVEL) for the stereodecoder. This application is given in Figure 35. Another (internal) time constant is used to control the Highcut through the multipath detector Selecting the "internal influence" in the configuration byte the Stereo-Blend and/or the Highcut is automatically invoked during a multipath condition according to the voltage appearing at the MP_OUT-pin.
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Figure 36. Blockdiagram of the Multipath-Detector
11.5 Quality Detector The TDA7405 offers a quality detector output which gives a voltage representing the FM-reception conditions. To calculate this voltage the MPX-noise and the multipath-detector output are summed according to the following formula : VQual = 1.6 (VNoise-0.8 V)+ a (REF5V-VMpout). The noise-signal is the PEAK-signal without additional influences (see noiseblanker description). The factor 'a' can by programmed to 0.7 .... 1.15. The output is a low impedance output able to drive external circuitry as well as simply fed to an AD-converter for RDS applications.
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11.6 Dual-MPX Mode The TDA7405 is able to support a twin tuner concept via the Dual-MPX-Mode. In this configuration the MPX-pin and the MD2G-pin are acting as MPX1 and MPX2 inputs. The DC-Voltage at the MD2-pin controls whether one or both MPX-signals are used to decode the stereo FM-signal. It is designed as a window-comparator with the characteristic shown in Figure 36 (Please note that the thresholds have a hysteresis of 500mV). In this mode the stereodecoder highohmic-mute mutes both inputs in parallel. Figure 37. Blockdiagram Dual MPX
Table 10. Pin-Configuration DMPX-/WSM-Mode
Dual MPX off off on on Weak-Signal Mute off on off on AMIF(12) AMIF-In WSM-TC AMIF-In WSM-TC DMPXC(25) not used WSM-In DMPC-Cntrl WSM-In MPX2(26) not used WSM-Out MPX2 WSM-Out MD2(43) MD2-In MD2-In MD2-In DMPC-Cntrl MD2G(44) MD2-Gnd MD2-Gnd MD2-Gnd MPX2
11.7 W eak-Signal Mute For use with front-ends which do not support a weak-signal-mute function the TDA7405 offers this feature as well. If this mode is enabled the pins 29 and 30 are used as an AC-coupling behind the Mute-Stage (see blockdiagram). In parallel pin 12 (AMIF) is switched internally to realize a mute time-constant with fast attack- and slow decay-time.
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Figure 38. Weak-Signal Mute-Depth @ 0.5V Threshold
5
0
-5
- 10
Mute Depth / dB
- 15
- 20
- 25
- 30
- 35
- 40 0.0 0.1 0.2 0.3 0.4 Level Voltage / V 0.5 0.6 0.7 0.8
Figure 39. Weak-Signal Mute-Threshold @ 24dB Mute-Depth
5
0
-5
-10
Mute Depth / dB
-15
-20
-25
-30 0.0 0.1 0.2 0.3 0.4 Level Voltage / V 0.5 0.6 0.7 0.8
11.8 Stereodecoder Testmode During the Testmode, which can be activated by setting bit D0 and bit D1 of the stereodecoder testing-byte, several internal signals are available at the FD2R+ pin. During this mode the input resistance of 100kOhm is disconnected from the pin. The internal signals available are shown in the Data-byte specification.
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12 I²C BUS INTERFACE
12.1 Interface Protocol The interface protocol comprises: -a start condition (S) -a chip address byte (the LSB bit determines read / write transmission) -a subaddress byte -a sequence of data (N-bytes + acknowledge) -a stop condition (P)
CHIP ADDRESS MSB LSB MSB S 1 0 0 0 1 1 0 R/W ACK C AZ SUBADDRESS LSB MSB A ACK DATA 1 ... DATA n LSB DATA ACK P
I
A
A
A
A
S = Start R/W ="0" -> Receive-Mode (Chip could be programmed by P) "1" -> Transmission-Mode (Data could be received by P) ACK = Acknowledge P = Stop MAX CLOCK SPEED 500kbits/s 12.1.1 Auto increment If bit I in the subaddress byte is set to "1", the autoincrement of the subaddress is enabled. 12.1.2 TRANSMITTED DATA (send mode)
MSB X X X X X P ST LSB SM
SM = Soft mute activated ST = Stereo P = Pause X = Not Used The transmitted data is automatically updated after each ACK. Transmission can be repeated without new chipaddress. 12.1.3 Reset Condition A Power-On-Reset is invoked if the Supply-Voltage is below than 3.5V. After that the following data is written automatically into the registers of all subaddresses :
MSB 1 1 1 1 1 1 1 LSB 0
The programming after POR is marked bold-face / underlined in the programming tables. With this programming all the outputs are muted to VREF (VOUT= VDD/2).
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12.2 SUBADDRESS (receive mode)
MSB I2 0 1 0 1 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 0 0 0 0 1 1 1 1 0 0 0 0 1 1 1 1 0 0 0 0 1 1 1 1 0 0 0 0 1 1 1 1 0 0 1 1 0 0 1 1 0 0 1 1 0 0 1 1 0 0 1 1 0 0 1 1 0 0 1 1 0 0 1 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 I1 I0 A4 A3 A2 A1 LSB FUNCTION A0 Compander Hold off on AutoZero Remain off on Auto-Increment Mode off on Subaddress Main Source Selector Loudness Volume Treble Bass Mixing Programming SoftMute Voice-Band Second Source Selector Equalizer Frequencies Equalizer-Config. / Bass Compander Configuration Audioprocessor I Configuration Audioprocessor II Equalizer Low-Filter Equalizer High-Filter Speaker attenuator LF Speaker attenuator RF Speaker attenuator LR Speaker attenuator RR Mixing Level Control Testing Audioprocessor Stereodecoder Noise-Blanker I Noise-Blanker II AM / AM-Noiseblanker High-Cut Control Fieldstr. & Quality Multipath-Detector Stereodecoder Adjustment Configuration Stereodecoder Testing Sterodecoder
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12.3 DATA BYTE SPECIFICATION The status after Power-On-Reset is marked bold-face / underlined in the programming tables. Table 11. Main Selector (0)
MSB D7 D6 D5 D4 D3 D2 0 0 0 0 1 1 1 1 0 0 : 1 1 0 1 0 0 : 1 1 0 0 : 1 1 0 1 : 0 1 D1 0 0 1 1 0 0 1 1 LS B FUN C TIO N D0 0 1 0 1 0 1 0 1 Source Selector FD1 / SE2 SE3 F D2 SE1 M D2 MD1 / SE4 Stereodecoder AM Input Gain 0dB 1dB : 14dB 15dB M ut e off on
Table 12. Loudness (1)
MSB D7 D6 D5 D4 0 0 : 0 0 : 1 : 0 0 1 1 0 1 0 1 0 1 D3 0 0 : 1 1 : 0 : D2 0 0 : 1 1 : 0 : D1 0 0 : 1 1 : 1 : LS B FUN C TIO N D0 0 1 : 0 1 : 1 : Attenuation 0 dB -1 dB : -14 dB -15 dB : -19 dB not allowed Center Frequency 200Hz 400Hz 600Hz 800Hz Loudness Order First Order Second Order
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Table 13. Volume1) (2)
MSB D7 0 0 : 0 0 0 : 0 0 0 : 1 1 D6 0 0 : 0 0 0 : 0 1 1 : 1 1 D5 0 0 : 0 0 0 : 1 0 0 : 0 0 D4 0 0 : 1 1 1 : 1 0 0 : 1 1 D3 0 0 : 1 1 1 : 1 0 0 : 1 1 D2 0 0 : 0 0 0 : 1 0 0 : 1 1 D1 0 0 : 0 0 1 : 1 0 0 : 1 1 LSB ATTENUATION D0 0 1 : 0 1 0 : 1 0 1 : 0 1 Gain/Attenuation (+32.0dB) (+31.5dB) : +20.0dB +19.5dB +19.0dB : +0.5dB 0.0dB -0.5dB : -79.0dB -79.5dB
Note: 1. It is not recommended to use a gain more than 20dB for system performance reason. In general, the max. gain should be limited by software to the maximum value, which is needed for the system.
Table 14. Treble Filter (3)
MSB D7 D6 D5 D4 0 0 : 0 0 1 1 : 1 1 0 0 1 1 0 1 0 1 0 1 D3 0 0 : 1 1 1 1 : 0 0 D2 0 0 : 1 1 1 1 : 0 0 D1 0 0 : 1 1 1 1 : 0 0 LSB D0 0 1 : 0 1 1 0 : 1 0 Treble Steps -15dB -14dB : -1dB 0dB 0dB +1dB : +14dB +15dB Treble Center-frequency 10.0 kHz 12.5 kHz 15.0 kHz 17.5 kHz Bass DC-Mode On Off FUNCTION
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Table 15. Bass Filter (4)
MSB D7 D6 D5 0 0 : 0 0 1 1 : 1 1 0 0 1 1 0 1 0 1 D4 0 0 : 1 1 1 1 : 0 0 D3 0 0 : 1 1 1 1 : 0 0 D2 0 0 : 1 1 1 1 : 0 0 D1 0 0 : 1 1 1 1 : 0 0 LSB FUNCTION D0 0 1 : 0 1 1 0 : 1 0 Bass Steps -15.5dB -15.0dB : -0.5 dB 0dB 0dB +0.5 dB : +15.0 dB +15.5 dB Bass Q-Factor 1.0 1.25 1.5 2.0
Table 16. Mixing Programming (5)
MSB D7 D6 D5 D4 D3 D2 D1 LSB FUNCTION D0 0 1 0 0 1 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 Mixing Mute enable Mixing Source Beep M D1 M D2 FM mono Mixing Target Speaker LF off Speaker LF on Speaker RF off Speaker RF on Speaker LR off Speaker LR on Speaker RR off Speaker RR on Loudness Main/2nd 2nd Main
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Table 17. SoftMute (6)
MSB D7 D6 D5 D4 D3 D2 D1 LSB D0 0 1 0 0 1 1 0 1 0 1 0 1 0 0 1 1 0 1 0 1 0 1 0 1 S of t M u t e On (Mute) Off MuteTime 0.48 ms 0.96 ms 123 ms 324 ms Influence on Stereodecoder Highohmic-Mute on off Influence on Pilot-detector Hold and MP-Hold on off Influence on SoftMute on off Beep Frequencies 500 Hz 780 Hz 1.8 kHz 19 kHz FUNCTION
Table 18. VoiceBand (7)
MSB D7 D6 D5 D4 D3 D2 D1 LSB D0 0 1 0 1 0 1 0 0 0 1 1 1 1 1 0 1 0 1 0 0 1 1 0 0 1 1 0 1 0 1 0 1 0 1 FUNCTION Voice-Band Low-Pass Enable Filter off Filter on Voice-Band Low-Pass Frequency 3 kHz 6 kHz Voice-Band High-Pass Enable Filter off Filter on High-Pass Cut-Off-Frequency 90Hz 135Hz 180Hz 215Hz 300Hz 450Hz 600Hz 750Hz Anti-Clipping Enable on off Anti-Clipping Input MP-In AM
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Table 19. Second Source Selector (8)
MSB D7 D6 D5 D4 D3 D2 0 0 0 0 1 1 1 1 0 0 : 1 1 0 1 0 0 : 1 1 0 0 : 1 1 0 1 : 0 1 D1 0 0 1 1 0 0 1 1 LS B D0 0 1 0 1 0 1 0 1 Source Selector FD1 / SE2 SE3 FD2 SE1 MD2 MD1 / SE4 Stereodecoder AM Input Gain 0dB 1dB : 14dB 15dB Mute off on FUNCTION
Table 20. Equalizer (9)
MS B D7 D6 D5 D4 D3 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 0 0 0 0 1 1 1 1 0 0 0 0 1 1 1 1 0 0 1 1 0 0 1 1 0 0 1 1 0 0 1 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 D2 0 0 0 0 1 1 1 1 0 0 0 0 1 1 1 1 D1 0 0 1 1 0 0 1 1 0 0 1 1 0 0 1 1 LS B D0 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 FUNCTION Frequencies EQ Low-Filter 63 Hz 74 Hz 88 Hz 105 Hz 125 Hz 149 Hz 177Hz 210 Hz 250 Hz 297 Hz 353 Hz 421 Hz 500 Hz 595 Hz 707 Hz 841 Hz Frequencies EQ High-Filter 297 Hz 353 Hz 421 Hz 500 Hz 595 Hz 707 Hz 841 Hz 1.0 kHz 1.19 kHz 1.41 kHz 1.68 kHz 2.0 kHz 2.38 kHz 2.83 kHz 3.36 kHz 4.0 kHz
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Table 21. EQ-Configuration / Bass (10)
MSB D7 D6 D5 D4 D3 D2 D1 0 0 1 1 0 0 1 1 0 1 0 0 0 0 1 1 1 1 0 0 1 1 0 0 1 1 0 1 0 1 0 1 0 1 0 1 0 1 LSB D0 0 1 0 1 EQ Filter Rear Path no Filter High-Filter Low-Filter High+Low-Filter EQ Filter Front Path no Filter High-Filter Low-Filter High+Low-Filter AM Noisebl. SoftUnMute On Off Bass Center-Frequency 60Hz 80Hz 70Hz 90Hz 100Hz 130Hz 150Hz 200Hz FUNCTION
Table 22. Compander (11)
MSB D7 D6 D5 D4 D3 D2 D1 0 0 1 1 0 0 1 1 0 0 1 1 0 0 0 0 1 1 1 1 0 1 0 1 0 1 0 0 1 1 0 0 1 1 0 1 0 1 0 1 0 1 0 1 0 1 LSB D0 0 1 0 1 FUNCTION Activity / Reference Level off 0.5VRMS 1VRMS 2VRMS Attack-Times 6 ms 12ms 24ms 49ms Release-Times 390ms 780ms 1.17s 1.56s SoftStep-Time1) 160s 320s 640s 1.28ms 2.56ms 5.12ms 10.2ms 20.4ms Compander max. Gain 29dB 19dB
Note: 1. The SoftStep-Times are only programmable while the Compander is not used.
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Table 23. Configuration Audioprocessor I (12)
MSB D7 D6 D5 D4 D3 D2 D1 LSB D0 0 1 0 1 0 1 0 1 0 0 1 1 0 0 1 1 0 1 0 1 0 1 0 1 FUNCTION Compander Source Main Selector Second Source Selector SoftStep off on Main Loudness flat Filter ON Second Loudness flat Filter ON Front Speaker Mute Second Source internal coupled Main Source AC-coupled Main Source internal coupled Rear Speaker Mute Second Source internal coupled Main Source AC-coupled Main Source internal coupled
Table 24. Configuration Audioprocessor II (13)
MSB D7 D6 D5 D4 D3 D2 D1 LSB D0 0 1 0 0 1 1 0 1 0 0 1 1 0 1 0 1 0 1 0 1 0 1 0 1 Pause Detector off on Pause ZC Window 160mV 80mV 40mV not allowed FD1 Mode single ended differential FD1 Attenuation -12dB -6dB -6dB 0dB FD2 Attenuation -6dB 0dB MD1 Mode single ended differential FUNCTION
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Table 25. Equalizer Low-Filter (14)
MSB D7 D6 D5 D4 0 0 : 0 0 1 1 : 1 1 0 0 1 1 0 1 0 1 0 1 D3 0 0 : 1 1 1 1 : 0 0 D2 0 0 : 1 1 1 1 : 0 0 D1 0 0 : 1 1 1 1 : 0 0 LSB FUNCTION D0 0 1 : 0 1 1 0 : 1 0 Gain / Attenuation -15dB -14dB : -1dB 0dB 0dB +1dB : +14dB +15dB Equalizer Q 1 2 3 4 Pause-Detector Source Rear Input-Selector Front Input-Selector
Table 26. Equalizer High-Filter (15)
MSB D7 D6 D5 D4 0 0 : 0 0 1 1 : 1 1 0 0 1 1 0 1 0 1 0 1 D3 0 0 : 1 1 1 1 : 0 0 D2 0 0 : 1 1 1 1 : 0 0 D1 0 0 : 1 1 1 1 : 0 0 LSB FUNCTION D0 0 1 : 0 1 1 0 : 1 0 Gain / Attenuation -15dB -14dB : -1dB 0dB 0dB +1dB : +14dB +15dB Equalizer Q 1 2 3 4 Switch Qual.-Detector Noise Content Off On
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Table 27. Speaker, Subwoofer and Mixer Level-Control (16-20) The programming of all Speaker-, Subwoofer and Mixing Level-Controls are the same.
MSB D7 1 : 1 1 0 0 : 0 0 : 0 0 x D6 0 : 0 0 0 0 : 0 0 : 1 1 1 D5 0 : 0 0 0 0 : 0 0 : 0 0 1 D4 0 : 0 0 0 0 : 0 1 : 0 0 x D3 1 : 0 0 0 0 : 1 0 : 1 1 x D2 1 : 0 0 0 0 : 1 0 : 1 1 x D1 1 : 0 0 0 0 : 1 0 : 1 1 x LSB ATTENUATION D0 1 : 1 0 0 1 : 1 0 : 0 1 x +15 dB : +1 dB 0 dB 0 dB -1 dB : -15 dB -16 dB : -78 dB -79 dB Mute
Table 28. Testing Audioprocessor (21)
MSB D7 D6 D5 D4 D3 D2 D1 LSB FUNCTION D0 0 1 0 0 0 0 1 1 1 1 0 1 0 1 0 1 0 1 0 0 1 1 0 0 1 1 0 1 0 1 0 1 0 1 Audioprocessor Testmode off on Test-Multiplexer Compander Log-Amp. Output Compander Low-Pass Output Compander DAC Output 200kHz Oscillator not allowed AM NB Mute NB-Hold internal Reference Compander Testmode off on Clock external internal AZ Function off on SC-Clock Fast Mode Normal Mode
Note : This byte is used for testing or evaluation purposes only and must not set to other values than "11101110" in the application!
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Table 29. Stereodecoder (22)
MSB D7 D6 D5 D4 D3 D2 D1 LS B FUN C TIO N D0 0 1 0 0 1 1 0 1 0 1 0 1 0 0 1 1 0 1 0 1 0 1 0 1 STD Unmuted STD Muted IN-Gain 11dB IN-Gain 8.5dB IN-Gain 6dB IN-Gain 3.5dB Input AM-Pin Input MPX-Pin Forced MONO MONO/STEREO switch automatically Pilot Threshold HIGH Pilot Threshold LOW Deemphasis Deemphasis Deemphasis Deemphasis 50s (37.5s1) 62.5s (46.9s1) 75s (56.3s1) 100s (75s1)
Note: 1. If Deemphasis-Shift enabled (Subaddr.26/Bit7 = 0)
Table 30. Noiseblanker I (23)
MSB D7 D6 D5 D4 D3 D2 D1 LS B FUN C TIO N D0 0 1 0 0 0 0 1 1 1 1 0 0 1 1 0 0 1 1 0 1 0 1 0 1 0 1 0 0 1 1 0 0 1 1 0 1 0 1 0 1 0 1 Noiseblanker off Noiseblanker on Low Threshold 65mV Low Threshold 60mV Low Threshold 55mV Low Threshold 50mV Low Threshold 45mV Low Threshold 40mV Low Threshold 35mV Low Threshold 30mV Noise Noise Noise Noise Controlled Controlled Controlled Controlled Threshold Threshold Threshold Threshold 320mV 260mV 200mV 140mV
Overdeviation Adjust 2.8V Overdeviation Adjust 2.0V Overdeviation Adjust 1.2V Overdeviation Detector OFF
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Table 31. Noiseblanker II (24)
MSB D7 D6 D5 D4 D3 D2 D1 LS B D0 0 1 0 0 1 1 0 0 1 1 0 0 1 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 FUN C TIO N PEAK charge current low high Fieldstrength adjust 2.3V 1.8V 1.3V O FF Blank Time FM / AM 38s / 1.2ms 25.5s / 800s 32s / 1.0s 22s / 640s Noise Rectifier Discharge Resistor R = infinite RDC = 56k RDC = 33k RDC = 18k Strong Multipath influence on PEAK 18k off on (18k discharge if VMPout< 2.5V)
Table 32. AM / FM-Noiseblanker (25)
MSB D7 D6 D5 D4 D3 D2 D1 LS B D0 0 1 0 0 0 0 1 1 1 1 0 0 1 1 0 1 0 1 0 1 0 1 0 0 1 1 0 0 1 1 0 1 0 1 0 1 0 1 FUN C TIO N Stereodecoder Mode FM AM AM Rectifier Gain 6dB 8dB 10dB 12dB 14dB 16dB 18dB 20dB Rectifier Cut-Off Frequency 14.0kHz 18.5kHz 28.0kHz 56.0kHz Overdeviation Time Constant on off AM Blank-Mode High-Ohmic Mute Sample&Hold
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Table 33. High-Cut (26)
MSB D7 D6 D5 D4 D3 D2 D1 LS B D0 0 1 0 0 1 1 0 0 1 1 0 0 1 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 High-Cut off on max. High-Cut 2dB 5dB 7dB 10dB VHCH to be at 42% REF5V 50% REF5V 58% REF5V 66% REF5V VHCL to be at 16.7% VHCH 22.2% VHCH 27.8% VHCH 33.3% VHCH Deemphasis Shift On Off FUN C TIO N
Table 34. Fieldstrength Control (27)
MS B D7 D6 D5 D4 D3 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 0 0 1 1 0 0 1 1 0 1 0 1 0 1 0 1 D2 0 0 0 0 1 1 1 1 0 0 0 0 1 1 1 1 D1 0 0 1 1 0 0 1 1 0 0 1 1 0 0 1 1 LS B D0 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 VSBL to be at 20.0% REF5V 23.3% REF5V 26.6% REF5V 30.0% REF5V 33.3% REF5V 36.6% REF5V 40.0% REF5V 43.3% REF5V 46.6% REF5V 50.0% REF5V 53.3% REF5V 56.6% REF5V 60.0% REF5V 63.3% REF5V 66.6% REF5V 70.0% REF5V Quality Detector Coefficient a=0.7 a=0.85 a=1.0 a=1.15 HCC-Level-Shift (only Level through MPD) 0.0V 500mV 1.0 V 1.5 V FUNCTION
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Table 35. Multipath Detector (28)
MSB D7 D6 D5 D4 D3 D2 D1 LS B FUN C TIO N D0 0 1 0 0 1 1 0 0 1 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 Fast Load on off Bandpass Gain 6dB 12dB 16dB 18dB Rectifier Gain Gain = 7.6dB Gain = 4.6dB Gain = 0dB disabled Charge Current at MP-Out 0.25A 0.50A Multipath on High-Cut Decay-Time 2 ms 10ms Multipath influence on PEAK Discharge off -1V/ms
Table 36. Stereodecoder Adjustment (29)
MSB D7 0 0 0 : 0 : 0 1 1 1 : 1 : 1 0 0 0 : 1 0 0 0 : 1 0 0 1 : 1 0 1 0 : 1 D6 D5 D4 D3 D2 0 0 0 : 1 : 1 0 0 0 : 1 : 1 D1 0 0 1 : 0 : 1 0 0 1 : 0 : 1 LS B FUN C TIO N D0 0 1 0 : 0 : 1 0 1 0 : 0 : 1 Roll-Off Compensation not allowed 7.2% 9.4% : 13.7% : 20.2% not allowed 19.6% 21.5% : 25.3% : 31.0% LEVEL Gain 0dB 0.4dB 0.8dB : 6dB
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Table 37. Stereodecoder Configuration (30)
MSB D7 D6 D5 D4 D3 D2 D1 LS B D0 0 1 0 1 0 1 0 1 0 1 0 1 0 0 1 1 0 1 0 1 1 x 1 x FUN C TIO N Multipath Influence on High-Cut On Off Multipath Influence on Stereo-Blend On Off Level-Input over Multipath-Detector1 On Off Dual MPX Mode On Off Weak-Signal-Mute on off WSMute Threshold 0.3 V 0.5V WS-Mute-Depth -20 dB -24 dB -28 dB -32 dB
Note: 1. Using the Multipath Time-Constants for Stereo-Bland and High-Cut
Table 38. Testing Stereodecoder(31)
MSB D7 D6 D5 D4 D3 D2 D1 LS B D0 0 1 0 1 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 0 1 0 1 0 0 0 0 1 1 1 1 0 0 0 0 1 1 1 1 0 0 1 1 0 0 1 1 0 0 1 1 0 0 1 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 FUNCTION Main Testmode off on Stereodecoder Testmode off on Testsignals F228 NB threshold Level for Stereo-Blend Pilot magnitude VHCCL Pilot threshold VHCCH REF5V HO LDN NB Peak AM-Rectifier VCOCON; VCO Control Voltage VSBL Pilot threshold Level for High-Cut REF5V Audioprocessor Oscillator Off On Disable Noiseblanker @ FS > 2.5V On Off
Note : This byte is used for testing or evaluation purposes only and must not set to other values than "11111100" in the application
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Figure 40. TQFP44 (10 x 10) Mechanical Data & Package Dimensions
mm DIM. MIN. A A1 A2 B C D D1 D3 E E1 E3 e L L1 k 0.45 11.80 9.80 0.05 1.35 0.30 0.09 11.80 9.80 12.00 10.00 8.00 12.00 10.00 8.00 0.80 0.60 1.00 0.75 0.018 12.20 10.20 0.464 0.386 1.40 0.37 TYP. MAX. 1.60 0.15 1.45 0.45 0.20 12.20 10.20 0.002 0.053 0.012 0.004 0.464 0.386 0.472 0.394 0.315 0.472 0.394 0.315 0.031 0.024 0.039 0.030 0.480 0.401 0.055 0.015 MIN. TYP. MAX. 0.063 0.006 0.057 0.018 0.008 0.480 0.401 inch
OUTLINE AND MECHANICAL DATA
TQFP44 (10 x 10 x 1.4mm)
0 (min.), 3.5(typ.), 7(max.)
D D1 A A2 A1
33 34 23 22
0.10mm .004 Seating Plane
E1
B
44 1 11
12
E
B C L K
e
TQFP4410
0076922 D
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Table 39. Revision History
Date October 2001 May 2004 Revision 1 2 First Issue modified Electrical Characteristics and Stylesheet Description of Changes
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Information furnished is believed to be accurate and reliable. However, STMicroelectronics assumes no responsibility for the consequences of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of STMicroelectronics. Specifications mentioned in this publication are subject to change without notice. This publication supersedes and replaces all information previously supplied. STMicroelectronics products are not authorized for use as critical components in life support devices or systems without express written approval of STMicroelectronics. The ST logo is a registered trademark of STMicroelectronics. All other names are the property of their respective owners 2004 STMicroelectronics - All rights reserved STMicroelectronics GROUP OF COMPANIES Australia - Belgium - Brazil - Canada - China - Czech Republic - Finland - France - Germany - Hong Kong - India - Israel - Italy - Japan Malaysia - Malta - Morocco - Singapore - Spain - Sweden - Switzerland - United Kingdom - United States www.st.com
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