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| TDA7402 CARRADIO SIGNAL PROCESSOR PRODUCT PREVIEW s s s s s s s s s s s 3 STEREO INPUTS 3 MONO INPUTS DYNAMIC-COMPRESSION-STAGE FOR CD SOFTSTEP-VOLUME BASS, TREBLE AND LOUDNESS CONTROL VOICE-BAND-FILTER DIRECT MUTE AND SOFTMUTE INTERNAL BEEP FOUR INDEPENDENT SPEAKER-OUTPUTS STEREO SUBWOOFER OUTPUT INDEPENDENT SECOND SOURCESELECTOR FULL MIXING CAPABILITY PAUSE DETECTOR DESCRIPTION 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. TQFP44 ORDERING NUMBER: TDA7402 Digital Control: s s I2C-BUS INTERFACE Stereodecoder: s RDS MUTE s s NO EXTERNAL ADJUSTMENTS AM/FM NOISEBLANKER WITH SEVERAL TRIGGER CONTROLS PROGRAMMABLE MULTIPATH DETECTOR QUALITY DETECTOR OUTPUT s s March 2000 This is preliminary information on a new product now in development. Details are subject to change without notice. 1/59 TDA7402 PIN CONNECTION (Top view) ESD: All pins are protected against ESD according to the MIL883 standard. 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 THERMAL DATA Symbol R th j-pins Parameter Thermal Resistance Junction-pins max Value 65 Unit C/W SUPPLY Symbol VS IS SVRR Parameter Supply Voltage Supply Current Ripple Rejection @ 1kHz V S = 9V Audioprocessor (all Filters flat) Stereodecoder + Audioprocessor Test Conditio n Min. 7.5 Typ. 9 50 60 55 Max. 10 Unit V mA dB dB 2/59 TDA7402 BLOCK DIAGRAM 3/59 TDA7402 Audioprocessor Part Features: Input Multiplexer 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 4 frequencies Beep, Phone and Navigation mixable to all speaker-outputs 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 Compander dynamic range compression for use with CD 2:1 compression rate programmable max. gain Bass 2nd order frequency response center frequency programmable in 8 steps DC gain programmable + 15 x 1dB steps Treble 2nd order frequency response center frequency programmable in 4 steps +15 x 1dB steps Voice Bandpass 2nd order butterworth highpass filter with programmable cut-off frequency 2nd order butterworth lowpass filter with programmable cut-off frequency selectable flat-mode Speaker 4 independent speaker controls in 1dB steps control range 95dB separate Mute Subwoofer single-ended stereo output independent stereo level controls in 1dB steps control range 95dB separate Mute Mute Functions Pause Detector direct mute digitally controlled SoftMute with 4 programmable mute-times programmable threshold 4/59 TDA7402 ELECTRICAL CHARACTERISTICS VS = 9V; Tamb = 25C; RL = 10k; all gains = 0dB; f = 1kHz; unless otherwise specified Symbol INPUT SELECTOR Rin VCL SIN GIN MIN GIN MAX GSTEP VDC 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 2.2 80 -1 100 2.6 100 0 15 1 1 6 0.5 +1 130 k VRMS dB dB dB dB mV mV mV Parameter Test Conditio n Min. Typ. Max. Unit DIFFERENTIAL STEREO INPUTS Rin G CD Input Resistance (see Figure 1) Gain Differential only at true differential input 70 100 0 -6 -12 CMRR Common Mode Rejection Ratio V CM = 1VRMS @ 1kHz V CM = 1VRMS @ 10kHz e NO Output-Noise @ Speaker-Outputs 20Hz - 20kHz, flat; all stages 0dB 46 46 70 60 9 130 k dB dB dB dB dB V DIFFERENTIAL MONO INPUTS Rin CMRR Input Impedance Common Mode Rejection Ratio Differential V CM = 1VRMS @ 1kHz V CM = 1VRMS @ 10kHz BEEP CONTROL VRMS fBeep Beep Level Beep Frequency Mix-Gain = 6dB fBeep1 fBeep2 fBeep1 fBeep1 MIXING CONTROL MLEVEL Mixing Ratio Main / Mix-Source -6/-6 dB 350 600 780 1.56 2.4 mV Hz Hz kHz kHz 40 40 40 56 70 60 k dB dB 5/59 TDA7402 ELECTRICAL CHARACTERISTICS (continued) Symbol GMAX AMAX A STEP Max. Gain Max. Attenuation Attennuation Step Parameter Test Conditio n Min. Typ. 15 -79 1 Max. Unit dB dB dB MULTIPLEXER OUTPUT 1 ROUT RL CL VDC Output Impedance Output Load Resistance Output Load Capacitance DC Voltage Level 4.5 2 10 225 k nF V LOUDNESS CONTROL A STEP AMAX fPeak Step Resolution Max. Attenuation Peak Frequency fP1 fP2 fP3 fP4 VOLUME CONTROL GMAX AMAX A STEP EA Max. Gain Max. Attenuation Step Resolution Attenuation Set Error G = -20 to +20dB G = -80 to -20dB ET VDC 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 Low Threshold for SM-Pin2 80 100 0.48 0.96 123 324 1 dB ms ms ms ms V 0.1 0.5 -0.75 -4 15.5 79.5 0.5 0 0 +0.75 3 2 3 5 dB dB dB dB dB dB mV mV 1 19 200 400 600 800 dB dB Hz Hz Hz Hz 6/59 TDA7402 ELECTRICAL CHARACTERISTICS (continued) Symbol VTH high RPU VPU Parameter High Threshold for SM - Pin Internal pull-up resistor Internal pull-up Voltage Test Conditio n Min. 2.5 32 45 3.3 58 Typ. Max. Unit V k V Notes: 1. If configured as Multiplexer-Output 2. The SM-Pin is active low (Mute = 0) BASS CONTROL CRANGE A STEP fC Control Range Step Resolution Center Frequency fC1 fC2 fC3 fC4 fC5 fC6 fC7 fC8 Q BASS Quality Factor Q1 Q2 Q3 Q4 DCGAIN Bass-DC-Gain DC = off DC = on TREBLE CONTROL CRANGE A STEP fC Control Range Step Resolution Center Frequency fC1 fC2 fC3 fC4 +15 1 10 12.5 15 17.5 dB dB kHz kHz kHz kHz +15 1 60 70 80 90 100 130 150 200 1 1.25 1.5 2 0 4.4 dB dB dB dB Hz Hz Hz Hz Hz Hz Hz Hz 7/59 TDA7402 ELECTRICAL CHARACTERISTICS (continued) Symbol PAUSE DETECTOR1 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 Parameter Test Conditio n Min. Typ. Max. Unit SPEAKER ATTENUATORS Rin GMAX AMAX A STEP AMUTE EE VDC Input Impedance Max. Gain Max. Attenuation Step Resolution Output Mute Attenuation Attenuation Set Error DC Steps Adjacent Attenuation Steps 0.1 80 35 50 15 79 1 90 2 5 65 k dB dB dB dB dB mV Notes: 1. If configured as Pause-Output AUDIO OUTPUTS VCLIP RL CL ROUT VDC Clipping Level Output Load Resistance Output Load Capacitance Output Impedance DC Voltage Level 30 4.5 d = 0.3% 2.2 2 10 120 2.6 VRMS k nF W V VOICE BANDPASS fHP Highpass corner frequency fHP1 fHP2 fHP3 fHP4 fHP5 fHP6 fHP7 fHP8 90 135 180 215 300 450 600 750 Hz Hz Hz Hz Hz Hz Hz Hz 8/59 TDA7402 ELECTRICAL CHARACTERISTICS (continued) Symbol fLP Parameter Lowpass corner frequency fLP1 fLP2 SUBWOOFER ATTENUATORS Rin GMAX AATTN A STEP AMUTE EE VDC Input Impedance Max. Gain Max. Attenuation Step Resolution Output Mute Attenuation Attenuation Set Error DC Steps Adjacent Attenuation Steps 1 80 35 50 15 79 1 90 2 5 65 k dB dB dB dB dB mV Test Conditio n Min. Typ. 3 6 Max. Unit kHz kHz SUBWOOFER Lowpass fLP Lowpass corner frequency fLP1 fLP2 fLP3 Notes: 1. If programmed as Subwoofer Diff.-Output 80 120 160 Hz Hz Hz DIFFERENTIAL OUTPUTS1) RL load resistance at each output 1VRMS; AC coupled; THD=1% 2VRMS; AC coupled; THD=1% RDL load resistance differential 1VRMS; AC coupled; THD=1% 2VRMS; AC coupled; THD=1% CLMAX CDLMAX VOffset ROUT VDC eNO Capacitive load at each output Capacitive load differential DC Offset at pins Output Impedance DC Voltage Level Output Noise Output muted C Lmax at each Output to Ground C Lmax between Output terminals Output muted -10 30 4.5 6 1 2 2 4 10 5 10 k k k k nF nF mV V V COMPANDER GMAX max. Compander Gain Vi < -46dB Vi < -46dB, Anti-Clip=On 19 29 dB dB 9/59 TDA7402 ELECTRICAL CHARACTERISTICS (continued) Symbol tAtt Attack time Parameter tAtt1 tAtt2 tAtt3 tAtt4 tRel Release time tRel1 tRel2 tRel3 tRel4 VREF Compander Reference InputLevel (equals 0dB) V REF1 V REF2 V REF3 CF Compression Factor Output Signal / Input Signal Test Conditio n Min. Typ. 6 12 24 49 390 780 1.17 1.56 0.5 1.0 2.0 0.5 Max. Unit ms ms ms ms ms ms s s VRMS VRMS VRMS Notes: 1. If programmed as Subwoofer Diff.-Output GENERAL e NO Output Noise BW = 20Hz - 20kHz output muted 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 V IN = 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 3 10 106 100 0.005 0.05 100 0 0 1 2 V V dB dB % % dB dB dB 10/59 TDA7402 1.0 DESCRIPTION OF THE AUDIOPROCESSOR PART 1.1 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 1. Input-stages 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). 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. 11/59 TDA7402 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). Mono-differential Input 2 (MD2) The MD2-input has the same topology as MD1, but without the possibility to configure it to single ended. Single-ended stereo Input (SE1), single-ended mono input (AM) and FM-MPX input All single ended inputs offer an input impedance of 100k. The AM-pin can be connected by software to the input of the stereo-decoder in order to use the AM-noiseblanker and AM-High-Cut feature. 1.2 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. 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. 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 A619 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. 1.3 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 IICBus programming). 12/59 TDA7402 1.4 Loudness There are four parameters programmable in the loudness stage: 1.4.1 Attenuation Figure 2 shows the attenuation as a function of frequency at fP = 400Hz Figure 2. Loudness Attenuation @ f = 400Hz. P 0.0 -5.0 -10.0 dB -15.0 -20.0 -25.0 10.0 100.0 1.0K 10.0K Hz 1.4.2 Peak Frequency Figure 3 shows the four possible peak-frequencies at 200, 400, 600 and 800HzFigure 3: Loudness Center frequencies @ Attn. = 15dB Figure 3. 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 13/59 TDA7402 1.4.3 Loudness Order Different shapes of 1st and 2nd-Order Loudness Figure 4. 1st and 2nd Order Loudness @ Attn. = 15dB, P=400Hz f 0.0 -5.0 dB -10.0 -15.0 -20.0 10.0 100.0 Hz 1.0K 10.0K 1.4.4 Flat Mode In flat mode the loudness stage works as a 0dB to -19dB attenuator. 1.5 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 5). For timing purposes the Bit0 of the I2C-bus output register is set to 1 from the start of muting until the end of demuting. Figure 5. 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 . 14/59 TDA7402 1.6 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 6. 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. 1.7 Bass There are four parameters programmable in the bass stage: 1.7.1 Attenuation Figure 7 shows the attenuation as a function of frequency at a center frequency of 80Hz. Figure 7. Bass Control @ fC = 80Hz, Q = 1 15.0 10.0 5.0 dB 0.0 -5. 0 -10.0 -15.0 10 .0 10 0.0 Hz 1.0K 10 .0K 15/59 TDA7402 1.7.2 Center Frequency Figure 8 shows the eight possible center frequencies 60, 70, 80, 90, 100, 130, 150 and 200Hz. Figure 8. 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 1.7.3 Quality Factors Figure 9 shows the four possible quality factors 1, 1.25, 1.5 and 2. Figure 9. Bass Quality factors @ Gain = 14dB, C = 80Hz f 15.0 12.5 10.0 7.5 5.0 2.5 0.0 10.0 100.0 1.0K 10.0K 16/59 TDA7402 1.7.4 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 10. Bass normal and DC Mode @ Gain = 14dB, C = 80Hz f 15.0 12.5 10.0 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. 1.8 Treble There are two parameters programmable in the treble stage: 1.8.1 Attenuation Figure 11 shows the attenuation as a function of frequency at a center frequency of 17.5kHz. Figure 11. Treble Control @ f = 17.5kHz C 15.0 10.0 5.0 0.0 -5.0 -10.0 -15.0 10.0 100.0 1.0K 10.0K 17/59 TDA7402 1.8.2 Center Frequency Figure 12 shows the four possible center frequencies 10k, 12.5k, 15k and 17.5kHz. Figure 12. 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 1.9 Subwoofer Application Figure 13. Subwoofer Application with LPF 80/120/160Hz and HPF 90/135/180Hz 0.0 -10.0 -20.0 dB -30.0 -40.0 -50.0 10.0 100.0 Hz 1.0K 10.0K Both filters, the lowpass- as well as the highpass-filter, have butterworth characteristic so that their cut-off frequencies are not equal but shifted by the factor 1.125 to get a flat frequency response. 18/59 TDA7402 1.10 Voice-Band Application Figure 14. VoiceBand Application with HPF 300/450/600/750Hz and LPF 3k/6kHz 0.0 -10.0 -20.0 dB -30.0 -40.0 -50.0 10.0 100.0 Hz 1.0K 10.0K 19/59 TDA7402 1.11 Compander Signal-Compression A fully integrated signal-compressor with programmable Attack- and Decay-times is present in the A619 (see Figure 15). 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 1Bit/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 InGainstage 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 15. Compander Block Diagram 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 20/59 TDA7402 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 29dB. 1.11.1Characteristic To achieve the desired compression characteristic like shown below the volume has to be decreased by 4dB. Figure 16. Compander Characteristic 0 -8dB 2:1 1.11.2I C -BUS-Timing During the Compander is working a volumeword 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 while 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 companderON is the following: -10 Output Level -20 dB -30 -38dB -40 15dB -50 -60 0 -10 -20 -30 -40 -50 -60 Input Level dB 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 6ms 12ms 24ms 48ms SoftStep-Time 0.16ms 0.32ms 0.64ms 1.28ms 1.12 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 I C-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. 21/59 TDA7402 1.13 Output Selector The output-selector allows to connect the main- or the second-source to the Front-, Rear and Subwoofer 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 17). In addition to this stage allows to setup different applications by IIC-Bus programming. In figure 18 to 20 three examples are given. Figure 17. Output Selector 1.14 Subwoofer Several different applications are possible with the Subwoofer-circuit: 1. Subwoofer-Filter OFF a. Main-source stereo (AC-coupled) b. Second-source stereo (DC-coupled) c. Main-source mono-differential (DC-coupled) d. Second-source mono-differential (DC-coupled) 2. Subwoofer-Filter ON a. Main-source mono-differential (DC-coupled) b. Second-source mono-differential (DC-coupled) c. Center-Speaker-Mode (filtered mono signal at SWL, unfiltered mono signal at SWR) In all applications the phase of the output-signal can be configured to be 0 or 180 . In the Center-SpeakerMode only at the filtered output the phase is changed. 22/59 TDA7402 Figure 18. Application1 using internal Highpass- and mono Low-pass-Filter Figure 19. Application2 using internal Highpass- and external stereo Low-pass-Filter 23/59 TDA7402 Figure 20. Application3 using pure external Filtering (e.g. DSP) 1.15 Speaker-Attenuator and Mixing A Mixing-stage is placed after each speaker-attenuator and can be set independly to mixing-mode. Having a full volume for the Mix-signal the stage offers a wide flexibility to adapt the mixing levels. Figure 21. Output Selector 24/59 TDA7402 1.16 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. 2.0 STEREODECODER PART 2.1 FEATURES: s s s s s s s s s s 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 2.2 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 Rin Gmin Gmax Gstep SVRR a THD 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 V ripple = 100mV, f = 1kHz Test Conditio n Input Gain = 3.5dB Min. Typ. 0.5 100 3.5 11 2.5 60 50 0.02 91 0.3 Max. 1.25 Unit Vrms k dB dB dB dB dB % dB S+ N N MONO/STEREO-SWITCH VPTHST1 VPTHST0 Pilot Threshold Voltage Pilot Threshold Voltage for Stereo, PTH = 1 for Stereo, PTH = 0 for Mono, PTH = 1 15 25 12 mV mV mV VPTHMO1 Pilot Threshold Voltage 25/59 TDA7402 2.2 ELECTRICAL CHARACTERISTICS (continued) Symbol Parameter Test Conditio n for Mono, PTH = 0 Min. Typ. 19 Max. Unit mV VPTHMO0 Pilot Threshold Voltage PLL f/f Capture Range 0.5 % DEEMPHASIS and HIGHCUT DeempFM Deemphasis Timeconstants FM V LEVEL >> VHCH V LEVEL >> VHCH V LEVEL >> VHCH V LEVEL >> VHCH MFM Highcut Timeconstant Multiplier FM V LEVEL << VHCL 50 62.5 75 100 3 37.5 47 56 75 3.7 5 0 6 s s s s DeempAM Deemphasis Timeconstants AM V LEVEL >> VHCH V LEVEL >> VHCH V LEVEL >> VHCH V LEVEL >> VHCH s s s s M AM REF5V Lmin L maxs L Gstep Highcut Timeconstant Multiplier AM V LEVEL << VHCL Internal Reference Voltage min. LEVEL Gain max. LEVEL Gain LEVEL Gain Step Resolution 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 V dB dB dB %REF5V %REF5V %REF5V %REF5V %REF5V %REF5V 0.4 20 70 3.3 42 66 8.4 17 33 4.2 VSBL min 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 %VHCH %VHCH %REF5V Carrier and harmonic suppression at the output 19 38 Pilot Signal f=19kHz Subcarrier f=38kHz 50 75 dB dB 26/59 TDA7402 2.2 ELECTRICAL CHARACTERISTICS (continued) Symbol 57 76 Parameter Subcarrier f=57kHz Subcarrier f=76kHz Test Conditio n Min. Typ. 62 90 Max. Unit dB dB Intermodulation (Note 2.3.1) 2 3 fmod=10kHz, fspur=1kHz fmod=13kHz, fspur=1kHz 65 75 dB dB Traffic Radio (Note 2.3.2) 57 Signal f=57kHz 70 dB SCA - Subsidiary Communications Authorization (Note 2.3.3) 67 Signal f = 67kHz 75 dB ACI - Adjacent Channel Interference (Note 2.3.4) 114 190 Signal f=114kHz Signal f=190kHz 95 84 dB dB 2.3 NOTES TO THE CHARACTERISTICS 2.3.1 Intermodulation Suppression V O ( s ignal ) ( at1kHz ) 2 = -------------------------------------------------------------- ; f = ( 2 10k Hz ) - 19kH z VO ( spurious )( at1kHz ) s V O ( s ignal ) ( at 1kHz ) ---------------------------------------------- -f = ( 3 13k H z) - 38k H z ; 3 = ----------------VO ( spuri ous )( at1kHz ) s measured with: 91% pilot signal; fm = 10kHz or 13kHz. 2.3.2 Traffic Radio (V.F.) Suppression V O ( signal ) ( at1kHz ) 57 ( V.W.F) = ---------------------------------------------------------------------------------------- V O ( s purious ) ( at1kHz 23k Hz) measured with: 91% stereo signal; 9% pilot signal; fm=1kHz; 5% subcarrier (f=57kHz, fm=23Hz AM, m=60%) 2.3.3 SCA ( Subsidiary Communications Authorization ) VO ( s ignal )( at1kHz ) ; 67 = --------------------------------------------------------------- -f s = ( 2 38kH z ) - 67kH z VO ( spuri ous ) ( at1kHz ) measured with: 81% mono signal; 9% pilot signal; fm=1kHz; 10%SCA - subcarrier ( fS = 67kHz, unmodulated ). 27/59 TDA7402 2.3.4 ACI ( Adjacent Channel Interference ) VO ( s ignal )( at1kHz ) 114 = --------------------------------------------------------------- -f s = 110k Hz - ( 3 38kH z ) ; VO ( spurious ) ( at4kHz ) VO ( s ignal )( at1kHz ) 190 = --------------------------------------------------------------- -f s = 186k Hz - ( 5 38kH z ) ; VO ( spurious ) ( at4kHz ) measured with: 90% mono signal; 9% pilot signal; fm=1kHz; 1% spurious signal ( fS = 110kHz or 186kHz, unmodulated). 2.4 NOISE BLANKER PART 2.4.1 Features: s s s s s s s s 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 2.4.2 ELECTRICAL CHARACTERISTICS All parameters measured in FM mode if not otherwise specified. Symbol V TR Parameter Trigger Threshold 1) Test Condition 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 V RECT Rectifier Voltage VMPX=0mV VMPX=50mV, f=150kHz VMPX=200mV, f=150kHz Min. Typ. 30 35 40 45 50 55 60 65 260 220 180 140 0.9 1.7 3.5 Max. Unit mVOP mVOP mVOP mVOP mVOP mVOP mVOP mVOP mVOP mVOP mVOP mVOP V V V 28/59 TDA7402 2.4.2 ELECTRICAL CHARACTERISTICS (continued) Symbol Parameter Test Condition 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. Typ. 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. Unit VOP VOP VOP VOP V V V V s s s s ms s s s V/ms VRECTDEV Deviation dependent Rectifier Voltage 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 SR PEAK 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 R AMIF kOhm dB dB dB kHz kHz GAMIF,min min. gain AM IF GAMIF,max GAMIF,step max. gain AM IF step gain AM IF min. fc AM IF fAMIF,min fAMIF,max max. fc AM IF Notes: 1. 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. V in V op DC T im e T R T HIGH T F 29/59 TDA7402 Figure 22. Trigger Threshold vs. V PEAK V TH 2 60m V (0 0) 2 20m V (0 1) 1 80m V (1 0) 1 40m V (1 1) M IN . TR IG . THR ES H OL D NO IS E C ON TR OL LE D T RIG . TH RE S HO LD 6 5m V 8 S TE PS 3 0m V 0 .9 V 1.5 V V PEAK [V] Figure 23. Fig. 23: Deviation Controlled Trigger Adjustment VP E A K [V OP ] 00 2 .8 01 2 .0 10 1 .2 0 .9 D e te c to r o ff (11 ) 20 32 .5 45 75 D E V IA T ION [KH z] Figure 24. Fieldstrength Controlled Trigger Adjustment VP E A K MONO S TERE O 3V 2 .4 V ( 0 0 ) 1 .9 V (0 1 ) 1 .4 V (1 0 ) N O IS E A T C _ S B O F F (1 1) 0 .9 V n o i sy s ig n a l g o o d s ig n a l E' 30/59 TDA7402 2.5 MULTIPATH Detector 2.5.1 Features: s s s internal 19kHz band-pass filter programmable band-pass- and rectifier-gain selectable internal influence on Stereoblend and/or Highcut 2.5.2 ELECTRICAL CHARACTERISTICS Symbol fCMP GBPMP Parameter Center frequency of MultipathBandpass Bandpass Gain Test Condition stereodecoder locked on Pilottone G1 G2 G3 G4 GRECTMP 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 G1 Rectifier Gain G2 G3 ICHMP IDISMP Rectifier Charge Current Rectifier Discharge Current QUALITY DETECTOR A Multipath Influence Factor 00 01 10 11 0.70 0.85 1.00 1.15 31/59 TDA7402 3.0 FUNCTIONAL DESCRIPTION OF STEREODECODER Figure 25. Block diagram of Stereodecoder The stereodecoder-part of the A619 (see Fig. 25) contains all functions necessary to demodulate the MPX-signal 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. 3.1 Stereodecoder-Mute The A619 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. Fig. 26 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. 32/59 TDA7402 Figure 26. Signals during stereodecoder's SoftMute Figure 27. Signal-Control via SoftMute-Pin 3.2 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. 3.3 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 A619 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 A619 needs no external network in front of the MPX-pin. Within this range an adjustment to obtain at least 40dB 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 33/59 TDA7402 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. 3.4 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 Deemp or 2.7 x Deemp 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 Deemp...3 (3.7) x Deemp. 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 2.9. 3.5 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 A619 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. 3.6 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. 3.7 EVEL-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 fig. 32). 3.8 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 figs.28, 29). To adjust the external LEVEL-voltage to the internal range two values must be defined: the LEVEL gain LG and VSBL (see fig. 29). 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. 34/59 TDA7402 Figure 28. 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 29. Relation between internal and external LEVEL-voltages for setup of Stereoblend 70 20 3.9 Highcut Control The highcut control set-up is similar to the stereoblend control set-up : 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 fig. 30). Figure 30. Highcut characteristics 35/59 TDA7402 4.0 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 fig.31. Figure 31. 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. 4.1 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. 4.2 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 fig. 19). The low threshold is activ 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 fig. 22). 4.3 Additional Threshold Control Mechanism 4.3.1 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 36/59 TDA7402 of the normal noise-controlled trigger adjustment is fixed (fig. 24). 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. 4.3.2 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 fig. 23). 4.3.3 Multipath-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 A619 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 R Discharge=infinite and VMPout=2.5V AM mode of the Noiseblanker The A619 noiseblanker is also suitable for AM noise cancelling. The detector uses in AM mode the 450kHz unfiltered IF-output of the tuner for spike detection. A combination of programmable gain-stage and lowpassfilter forms an envelope detector which drives the noiseblanker's input via a 120kHz 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. 37/59 TDA7402 5.0 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, fig. 32). 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 fig. 32. 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. Figure 32. Blockdiagram of the Multipath-Detector 6.0 QUALITY DETECTOR The A619 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. 7.0 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. 38/59 TDA7402 8.0 DUAL MPX USAGE 8.1 Feature Description The A619 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 1 (Please note that the thresholds have a hysteresis of 500mV). In this mode the stereodecoder highohmic-mute mutes both inputs in parallel. Figure 33. 8.2 Configuration The Dual-MPX-Mode can be easily configured by setting bit 3 of subaddress 30 to LOW (see Byte 30 description and Application Diagram of fig. 35). 39/59 TDA7402 9.0 I C BUS INTERFACE 9.1 Interface Protocol s s s s s s 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 SUBADDRESS DATA 1....DATA n MSB S 1 LSB 0 0 1 1 0 MSB AZ LSB I AA AAA ACK MSB DATA LSB ACK P 0 R/W ACK C 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 9.2 Auto increment If bit I in the subaddress byte is set to "1", the autoincrement of the subaddress is enabled. 9.3 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. 9.4 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). 40/59 TDA7402 9.5 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 Subadd ress Main Source Selector Main Loudness Volume Treble Bass Mixing Programming SoftMute Voice-Band Second Source Selector Second Source Loudness Subwoofer-Config. / Bass Compander Configuration Audioprocessor I Configuration Audioprocessor II Subwoofer attenuator L Subwoofer attenuator R 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 41/59 TDA7402 9.6 DATA BYTE SPECIFICATION The status after Power-On-Reset is marked bold-face / underlined in the programming tables. 9.6.1 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 LSB FUNCTION D0 0 1 0 1 0 1 0 1 Source Selector FD1 / SE2 SE3 FD2 SE1 MD2 MD1 / SE4 Stereodecoder AM Inpu t Gain 0dB 1dB : 14dB 15dB Mute off on 9.6.2 Main 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 : LSB FUNCTION 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 Loud ness Order First Order Second Order 42/59 TDA7402 9.6.3 Volume (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: 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. 9.6.4 Treble Filter (3) MSB D7 D6 D5 D4 D3 D2 D1 LSB FUNCTION D0 Treble Steps -15dB -14dB : -1 dB 0 dB 0 dB +1 dB : +14 dB +15dB Treble Center-frequency 10.0 kHz 12.5 kHz 15.0 kHz 17.5 kHz Subwoof er+Center-Speaker Mode On Off 0 0 : 0 0 1 1 : 1 1 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 1 : 0 1 1 0 : 1 0 0 0 1 1 0 1 0 1 0 1 43/59 TDA7402 9.6.5 Bass Filter (4) 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 Bass Steps -15dB -14dB : -1 dB 0 dB 0 dB +1 dB : +14 dB +15dB Bass Q-Factor 1.0 1.25 1.5 2.0 Bass DC-Mode Off On 9.6.6 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 MD1 MD2 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 Stereo Subw. using internal Highpass-Filter On Off 44/59 TDA7402 9.6.7 Soft Mute (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 SoftMute On (Mute) Off Mutetime = 0.48ms Mutetime = 0.96ms Mutetime = 123ms Mutetime = 324 ms Influ ence on Stereodecoder Highoh mic-Mute on off Influ ence on Pilot-detector Hold and MP-Hold on off Influ ence on SoftMute on off Beep Frequencies 600 Hz 780 Hz 1.56 kHz 2.4 kHz FUNCTION 9.6.8 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 45/59 TDA7402 9.6.9 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 LSB FUNCTION D0 0 1 0 1 0 1 0 1 Source Selector FD1 / SE2 SE3 FD2 SE1 MD2 MD1 / SE4 Stereodecoder AM Inpu t Gain 0dB 1dB : 14dB 15dB Mute off on 9.6.10Second Loudness (9) 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 : LSB FUNCTION 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 46/59 TDA7402 9.6.11Subwoofer Configuration / Bass (10) MSB D7 D6 D5 D4 D3 D2 D1 0 0 1 1 0 1 0 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 LSB FUNCTION D0 0 1 0 1 Subwoofer Filter off 80Hz 120Hz 160Hz Subwoofer Outputs differential (mono) single ended (stereo) Subwoofer Source Second Source Main Source Subwoofer Phase 180 0 Bass Center-Frequency 60Hz 80Hz 70Hz 90Hz 100Hz 130Hz 150Hz 200Hz 47/59 TDA7402 9.6.12Compander (11) MSB D7 D6 D5 D4 D3 D2 D1 0 0 1 1 LSB FUNCTION D0 0 1 0 1 Activity / Reference Level off 0.5V RMS 1VRMS 2VRMS Attack-Times 6ms 12ms 24ms 49ms Release-Times 390ms 780ms 1.17s 1.56s 0 0 1 1 0 0 1 1 0 1 0 1 0 1 0 1 SoftStep-Time1) 160s 320s 640s 1.28ms 2.56ms 5.12ms 10.2ms 20.4ms Compander max. Gain 29dB 19dB 0 0 1 1 0 0 1 1 0 0 0 0 1 1 1 1 0 1 0 1 0 1 0 1 0 1 Notes: 1. The SoftStep-Times are only programmable while the Compander is not used. 48/59 TDA7402 9.6.13Configuration 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 Compander Source Main Selector Second Source Selector SoftStep off on Main Loudness flat Filter ON Second Loudn ess flat Filter ON Front Speaker not allowed Second Source internal coupled Main Source AC-coupled Main Source internal coupled Rear Speaker not allowed Second Source internal coupled Main Source AC-coupled Main Source internal coupled FUNCTION 9.6.14Configuration 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 Wind ow 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 49/59 TDA7402 9.6.15Speaker, Subwoofer and Mixer Level-Control (14-20) 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 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 ATTENUATION 9.6.16Testing 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-Multip lexer Compander Log-Amp. Output Compander Low-Pass Output Compander DAC Output 200kHz Oscillator not allowed not allowed 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! 50/59 TDA7402 9.6.17Stereodecoder (22) MSB D7 D6 D5 D4 D3 D2 D1 LSB FUNCTION 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 11 dB IN-Gain 8.5 dB IN-Gain 6 dB IN-Gain 3.5 dB 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) Notes: 1. If Deemphasis-Shift enabled (Subaddr.26/Bit7 = 0) 9.6.18Noiseblanker I (23) MSB D7 D6 D5 D4 D3 D2 D1 LSB FUNCTION 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 Low Low Low Low Low Low Low Threshold Threshold Threshold Threshold Threshold Threshold Threshold Threshold 65mV 60mV 55mV 50mV 45mV 40mV 35mV 30mV 320mV 260mV 200mV 140mV Noise Noise Noise Noise Controlled Threshold Controlled Threshold Controlled Threshold Controlled Threshold Overdeviation Overdeviation Overdeviation Overdeviation Adjust 2.8V Adjust 2.0V Adjust 1.2V Detector OFF 51/59 TDA7402 9.6.19Noiseblanker II (24) MSB D7 D6 D5 D4 D3 D2 D1 LSB FUNCTION 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 PEAK charge current low high Fieldstrength adjust 2.3V 1.8V 1.3V OFF 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) 0 1 9.6.20AM / FM-Noiseblanker (25) MSB D7 D6 D5 D4 D3 D2 D1 LSB FUNCTION D0 0 1 0 0 0 0 1 1 1 1 0 0 1 1 1 1 0 1 0 1 0 0 1 1 0 0 1 1 0 1 0 1 0 1 0 1 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 must be "1" 52/59 TDA7402 9.6.21High-Cut (26) MSB D7 D6 D5 D4 D3 D2 D1 LSB 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 FUNCTION 9.6.22Fieldstrength Control (27) MSB 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 LSB 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 53/59 TDA7402 9.6.23Multipath Detector (28) MSB D7 D6 D5 D4 D3 D2 D1 LSB FUNCTION 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 2ms 10ms Multipath influence on PEAK Discharge off -1V/ms 9.6.24Stereodecoder 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 LSB FUNCTION 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 54/59 TDA7402 9.6.25Stereodecoder Configuration (30) MSB D7 D6 D5 D4 D3 D2 D1 LSB FUNCTION D0 0 1 0 1 0 1 1 x 1 x 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 must be "1" 0 1 1 1 1 1 1 Notes: 1. Using the Multipath Time-Constants for Stereo-Bland and High-Cut 9.6.26Testing Stereodecoder(31) MSB D7 D6 D5 D4 D3 D2 D1 LSB FUNCTION D0 0 1 0 1 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 0 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 Main Testmode off on Stereodecoder Testmode off on Testsignals F228 NB threshold Level for Stereo-Blend Pilot magnitude VHCCL Pilot threshold VHCCH REF5V HOLDN NB Peak AM-Rectifier VCOCON; VCO Control Voltage VSBL Pilot threshold Level for High-Cut REF5V Audioprocessor Oscillator Off On must be "1" Note : This byte is used for testing or evaluation purposes only and must not set to other values than "11111100" in the application! 55/59 TDA7402 10.0 APPLICATION INFORMATION Figure 34. Application Diagram (standard configuration) TDA7402 56/59 TDA7402 Figure 35. Application Diagram (Dual MPX mode) TDA7402 57/59 TDA7402 Figure 36. DIM. MIN. A A1 A2 B C D D1 D3 e E E1 E3 L L1 K 0.45 0.05 1.35 0.30 0.09 12.00 10.00 8.00 0.80 12.00 10.00 8.00 0.60 1.00 0.75 0.018 1.40 0.37 mm TYP. MAX. 1.60 0.15 1.45 0.45 0.20 0.002 0.053 0.012 0.004 MIN. inch TYP. MAX. 0.063 0.006 0.055 0.014 0.057 0.018 0.008 0.472 0.394 0.315 0.031 0.472 0.394 0.315 0.024 0.039 0.030 OUTLINE AND MECHANICAL DATA TQFP44 (10 x 10) 0(min.), 3.5(typ.), 7(max.) D D1 A1 33 34 23 22 0.10mm .004 Seating Plane A A2 E1 B 44 1 11 12 E B e L C K TQFP4410 58/59 TDA7402 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. N o 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 (R) 2000 STMicroelectronics - All Rights Reserved STMicroelectronics GROUP OF COMPANIES Australia - Brazil - China - Finland - France - Germany - Hong Kong - India - Italy - Japan - Malaysia - Malta - Morocco - Singapore - Spain - Sweden - Switzerland - United Kingdom - U.S.A. http:/ /www.st.com 59/59 |
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