TDA7402TR STMicroelectronics, TDA7402TR Datasheet

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Features ■ 3 stereo inputs ■ 3 mono inputs ■ Dynamic-compression-stage for cd ■ Soft Step volume ■ Bass, treble and loudness control ■ Voice-band filter ■ Direct mute and Soft Mute ■ Internal beep ■ Four independent speaker-outputs ■ ...

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Contents Contents 1 Pin connections and block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 2 Electrical specifications ...

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TDA7402 3.11 Compander . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...

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Contents 6.1 Trigger path ...

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TDA7402 List of tables Table 1. Device summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...

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List of figures List of figures Figure 1. Pin connections (top view ...

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TDA7402 1 Pin connections and block diagram Figure 1. Pin connections (top view SE1L 1 SE1R 2 FD1L+/SE3L 3 FD1L-/SE2L 4 FD1R+/SE3R 5 FD1R-/SE2R 6 7 FD2L+ FD2L- 8 ...

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Pin connections and block diagram Figure 2. Block diagram ACINLF ACINLR ACINRF ACINRR SWINL SWINR ACOUTR ACOUTL 8/69 TDA7402 ...

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TDA7402 2 Electrical specifications 25° 10kΩ; all gains = 0dB 1kHz; unless otherwise specified. S amb L Table 2. Electrical characteristics Symbol Parameter Input selector R Input resistance in V Clipping ...

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Electrical specifications Table 2. Electrical characteristics (continued) Symbol Parameter Mixing control M Mixing ratio LEVEL G Max. gain MAX A Max. attenuation MAX A Attenuation step STEP (1) Multiplexer output R Output impedance OUT R Output load resistance L C ...

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TDA7402 Table 2. Electrical characteristics (continued) Symbol Parameter R Internal pull-up resistor PU V Internal pull-up voltage PU Bass control C Control range RANGE A Step resolution STEP f Center frequency C Q Quality factor BASS DC Bass-DC-gain GAIN Treble ...

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Electrical specifications Table 2. Electrical characteristics (continued) Symbol Parameter Speaker attenuator R Input impedance in G Max. gain MAX A Max. attenuation MAX A Step resolution STEP A Output mute attenuation MUTE E Attenuation set error steps ...

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TDA7402 Table 2. Electrical characteristics (continued) Symbol Parameter Subwoofer lowpass f Lowpass corner frequency LP (4) Differential outputs R load resistance at each output L R load resistance differential DL C Capacitive load at each output LMAX C Capacitive load ...

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Electrical specifications Table 2. Electrical characteristics (continued) Symbol Parameter General e Output noise NO S/N Signal to noise ratio d distortion S Channel separation left/right C E Total tracking error configured as multiplexer-output 2. The SM Pin ...

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TDA7402 3 Audioprocessor part 3.1 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 ...

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Audioprocessor part ● 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 ...

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TDA7402 3.2.1 Full differential stereo input 1 (FD1) The FD1 input is implemented as a buffered full-differential stereo stage with 100kΩ input impedance at each input. The attenuation is programmable in 3 steps from 0 to -12dB in order to ...

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Audioprocessor part The root cause of this procedure is, that after muting the stereo decoder (Step 1), the internal stereo decoder filters have to settle in order to perform a proper offset cancellation. 3.3.2 AutoZero remain In some cases, for ...

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TDA7402 3.4.3 Peak frequency Figure 5 shows the four possible peak-frequencies at 200, 400, 600 and 800Hz Figure 5. Loudness center frequencies @ Attn. = 15dB. 0.0 -5.0 dB -10.0 -15.0 -20.0 10.0 3.4.4 Loudness order Different shapes of 1st ...

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Audioprocessor part 3.5 Soft Mute The digitally controlled Soft Mute stage allows muting/demuting the signal with a I programmable slope. The mute process can either be activated by the Soft Mute pin the I C-bus. This slope ...

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TDA7402 3.7 Bass There are four parameters programmable in the bass stage: 3.7.1 Attenuation Figure 9 shows the attenuation as a function of frequency at a center frequency of 80Hz. Figure 9. Bass control @ f 15.0 10.0 5.0 dB ...

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Audioprocessor part 3.7.3 Quality factors Figure 11 shows the four possible quality factors 1, 1.25, 1.5 and 2. Figure 11. Bass quality factors @ Gain = 14dB, f 15.0 12.5 10.0 7.5 5.0 2.5 0.0 10.0 3.7.4 DC mode In ...

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TDA7402 3.8 Treble There are two parameters programmable in the treble stage: 3.8.1 Attenuation Figure 13. shows the attenuation as a function of frequency at a center frequency of 17.5kHz. Figure 13. Treble control @ f 15.0 10.0 5.0 0.0 ...

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Audioprocessor part 3.9 Subwoofer application Figure 15. 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 Both filters, the lowpass and the highpass-filter, have butterworth characteristics so that their cut off frequencies are ...

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TDA7402 3.11 Compander Signal compression A fully integrated signal compressor with programmable attack and decay times is present in the TDA7402 (see The compander consists of a signal level detection, an A/D Converter plus adder and the normal Soft Step ...

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Audioprocessor part 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 ...

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TDA7402 3.12 AC coupling In some applications additional signal manipulations are desired, for example surround sound or more band equalizing. For this purpose an AC coupling is placed before the speaker attenuator, which can be activated or internally shorted by ...

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Audioprocessor part 3.14 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 ...

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TDA7402 Figure 21. Application 2 using internal highpass and external stereo low pass filter MAIN SOURCE LEFT CHANNEL MAIN SOURCE RIGHT CHANNEL SECOND SOURCE LEFT CHANNEL SECOND SOURCE Figure 22. Application 3 using pure external filtering (e.g. DSP) MAIN SOURCE ...

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Audioprocessor part 3.15 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 ...

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TDA7402 4 Stereo decoder part 4.1 Stereo decoder part 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 ...

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Stereo decoder part Table 7. Stereo decoder electrical characteristics (continued) Symbol Parameter De-emphasis and highcut τ De-emphasis time constants FM DeempFM M Highcut time constant multiplier FM FM τ De-emphasis time constants AM DeempAM M Highcut time constant multiplier AM ...

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TDA7402 Table 7. Stereo decoder electrical characteristics (continued) Symbol Parameter Intermodulation (Note 4.3.1) α2 f =10kHz, f =1kHz mod spur α3 f =13kHz, f =1kHz mod spur Traffic Radio (Note 4.3.2) α57 Signal f=57kHz SCA - Subsidiary Communications Authorization (Note ...

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Stereo decoder part 4.3.4 ACI (adjacent channel interference) α114 α190 measured with: 90% mono signal; 9% pilot signal; fm=1kHz; 1% spurious signal (f = 110kHz or 186kHz, unmodulated). S 4.4 Noise blanker part 4.4.1 Noise blanker part features ● AM ...

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TDA7402 Table 8. Noise blanker electrical characteristics (continued) Symbol Parameter V Rectifier voltage RECT Deviation dependent V DE RECT rectifier voltage V Fieldstrength V controlled rectifier FS RECT voltage T Suppression pulse duration FM SFM T Suppression pulse duration AM ...

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Stereo decoder part Figure 24. Vn timing diagram Figure 25. Trigger threshold vs. V Figure 26. Deviation controlled trigger adjustment Figure 27. Field strength controlled trigger adjustment V PEAK » 3V 36/ ...

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TDA7402 4.5 Multipath detector 4.5.1 Multipath detector features ● internal 19kHz band pass filter ● programmable band pass and rectifier gain ● selectable internal influence on stereo blend and/or Highcut Table 9. Multipath detector electrical characteristics Symbol Center frequency of ...

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Functional description of stereo decoder 5 Functional description of stereo decoder Figure 28. Block diagram of stereo decoder INGAIN MPX 3.5 ... 11dB STEP 2.5dB 100K AM 100K AM-IF D00AU1135 The stereo decoder-part of the TDA7402 (see demodulate the MPX-signal ...

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TDA7402 Figure 29. Signals during stereo decoder's Soft Mute Figure 30. Signal control via Soft Mute pin SOFTMUTE 5.2 InGain + infilter The InGain stage allows adjustment of the MPX-signal to a magnitude of about 1V internally, which is the ...

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Functional description of stereo decoder the channel separation and the fieldstrength control are trimmed. The setup of the stereo blend characteristics which is programmable in a wide range is described in 5.4 De-emphasis and highcut The de-emphasis lowpass allows to ...

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TDA7402 5.8 Stereo blend control The stereo blend 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 ...

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Functional description of stereo decoder Figure 33. Highcut characteristics 42/69 LOWPASS TIME CONSTANT τ ' • 3.7 DEEMPHASIS SHIFT ON Deemp τ 3 • Deemp OFF τ Deemp τ ' Deemp VHCL D00AU1169 TDA7402 VHCH FIELDSTRENGHT ...

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TDA7402 6 Functional description of the noise blanker 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 ...

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Functional description of the noise blanker 6.3 Additional threshold control mechanism 6.3.1 Automatic threshold control by the stereo blend voltage Besides the noise controlled threshold adjustment there is an additional possibility for influencing the trigger threshold which depends on the ...

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TDA7402 7 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 ...

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Functional description of the multipath detector 7.2 Testmode During the testmode, which can be activated by setting bit D decoder testing byte, several internal signals are available at the FD2R+ pin. During this mode the input resistance of 100kOhm is ...

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TDA7402 bus interface 8.1 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 ...

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I C bus interface 8.4 Subaddress (receive mode) Table 12. Subaddress (receive mode) MSB 48/69 LSB Compander ...

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TDA7402 8.5 Data byte specification The status after power on reset is marked bold face / underlined in the programming tables. Table 13. Main selector (0) MSB ...

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I C bus interface Table 15. Volume (2) MSB ...

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TDA7402 Table 17. Bass filter (4) MSB Table 18. Mixing programming (5) MSB ...

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I C bus interface Table 19. Soft mute (6) MSB Table 20. Voiceband (7) MSB 52/69 LSB ...

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TDA7402 Table 20. Voiceband (7) (continued) MSB Table 21. Second source selector (8) MSB ...

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I C bus interface Table 22. Second loudness (9) MSB Table 23. Subwoofer configuration / Bass (10) MSB ...

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TDA7402 Table 24. Compander (11) MSB Note: The Soft Step times are only programmable while the ...

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I C bus interface Table 25. Configuration audioprocessor I (12) (continued) MSB Table 26. Configuration audioprocessor II (13) MSB D D ...

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TDA7402 Table 26. Configuration audioprocessor II (13) (continued) MSB Table 27. Speaker, subwoofer and mixer level-control (14-20) MSB ...

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I C bus interface Table 28. Testing Audioprocessor (21) MSB Note: This byte is used for testing or evaluation purposes only and must not set to other ...

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TDA7402 Table 29. Stereo decoder (22) (continued) MSB De-emphasis-Shift enabled (Subaddr.26/Bit7 = 0) Table 30. Noise blanker I (23) MSB D D ...

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I C bus interface Table 31. Noiseblanker II (24) MSB Table 32 noiseblanker (25) MSB ...

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TDA7402 Table 32 noiseblanker (25) (continued) MSB Table 33. High cut (26) MSB ...

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I C bus interface Table 34. Fieldstrength control (27) MSB Table 35. Multipath detector (28) MSB ...

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TDA7402 Table 35. Multipath detector (28) (continued) MSB Table 36. Stereo decoder adjustment (29) MSB ...

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I C bus interface Table 37. Stereo decoder configuration (30) MSB Using the multipath time-constants for stereo bland and high cut 64/69 LSB ...

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TDA7402 Table 38. Testing stereo decoder (31) MSB Note: This byte is used for testing ...

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Application information 9 Application information Figure 37. Application diagram (standard configuration) 220nF SEL 220nF SER 220nF FD1L+ 220nF FD1L- 220nF FD1R+ 220nF FD1R- 220nF FD2L+ 220nF FD2L- 220nF FD2R+ 220nF FD2R- 220nF AM 220nF MPX1 470nF MPOUT Figure 38. Application ...

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TDA7402 10 Package information In order to meet environmental requirements, ST (also) offers these devices in ECOPACK packages. ECOPACK is marked on the package and on the inner box label, in compliance with JEDEC Standard JESD97. The maximum ratings related ...

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Revision history 11 Revision history Table 39. Document revision history Date 26-Apr-2002 21-Jun-2004 26-Apr-2004 26-Apr-2006 23-Mar-2007 18-Sep-2008 68/69 Revision 1 Initial release 2 Technical migration from ST-PRESS to EDOCS 3 Revalidation 4 Minor text changes. Document reformatted. 5 Package change, ...

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... TDA7402 Information in this document is provided solely in connection with ST products. STMicroelectronics NV and its subsidiaries (“ST”) reserve the right to make changes, corrections, modifications or improvements, to this document, and the products and services described herein at any time, without notice. All ST products are sold pursuant to ST’s terms and conditions of sale. ...