TDA7420 MULTIFUNCTION AUDIO PROCESSOR CASSETTE PREAMPLIFIER: FORWARD/REVERSE INPUTS GROUND COMPATIBLE INTERNAL SWITCHES FOR EQUALIZATION INTERNAL ADJUSTMENT FOR TRAKING INTERNAL ADJUSTMENT FOR OUTPUT AMS: INPUT GAIN CONTROL ADJUSTABLE GAIN VERSUS FREQUENCY AUDIOPROCESSOR: INPUTS: 1 FULLY DIFFERENTIAL, 1 DIFFERENTIAL, 1 STEREO AND 1 MONO INPUT GAIN FROM 0 TO 15dB (1dB STEP) VOLUME CONTROL FROM +16 TO -63dB (1dB STEP) BASS AND TREBLE CONTROL FROM -18 TO 18dB (1dB STEP) DIRECT MUTE, SOFT MUTE AND RADIO MUTE FOUR INDEPENDENT OUTPUT STAGES: - ATTENUATION CONTROL FROM 0 TO -79dB (1dB STEP) - BEEP CONTROL (ON/OFF, FRONT/REAR) STEREO DECODER: ROLL-OFF ADJUSTMENT SELECTABLE DEEMPHASIS 19KHz CANCELLATION HIGH CUT CONTROL STEREO BLEND NOISE BLANKER AUTOMATIC THRESHOLD CONTROL AND PROGRAMMABLE TRIGGER THRESHOLD INTEGRATED HIGH PASS FILTER PACKAGE: TQFP64 (14x14) May 1998 TQFP 64 (14x14) ORDERING NUMBER: TDA7420 DESCRIPTION The TDA7420 I 2C bus controlled multifunction audio processor contains all signal processing blocks of a high performance car radio, including audioprocessor, stereodecoder, noise blanker, different mute functions, cassette preamplifier and AMS function. The use of BICMOS technology allows the implementation of several filter functions with switched capacitor techniques like fully integrated, adjustment free PLL Loop filter, pilot detector with integrator. This minimizes the number of external components. Due to a highly linear signal processing, using CMOS-switching techniques instead of standard bipolar multipliers, very low distortion and very low noise are obtained also in the stereodecoder part. Very low DC stepping is obtained by use of the BICMOS technology. 1/29 TDA7420 ABSOLUTE MAXIMUM RATINGS Symbol VS Parameter Operating Supply Voltage Value Unit 10 V Tamb Operating Temperature Range -40 to 85 °C Tstg Storage Temperature Range -55 to 150 °C EQRO PREOUT_R VCC_PRE CD_R+ CD_R- CD_L- CD_L+ L1 R1 AM_R AM_C AM_L COMPOSIT CREF CSM AC_IN1_L PIN CONNECTION 64 63 62 61 60 59 58 57 56 55 54 53 52 51 50 49 AC_IN1_R 1 48 EQRI AC_OUT1_R 2 47 INR2(FR) AC_OUT1_L 3 46 INR1(RR) TREBLE_L 4 45 GND_PRE TREBLE_R 5 44 INL1(RL) AC_OUT2_R 6 43 INL2(FL) AC_OUT2_L 7 42 EQLI AC_IN2_L 8 41 EQLO AC_IN2_R 9 40 PREOUT_L BASS2_R 10 39 EQSW BASS1_R 11 38 BEEP BASS2_L 12 37 OUT_RL BASS1_L 13 36 OUT_FL VCC 14 35 OUT_RR SDA 15 34 OUT_FR SCL 16 33 AMS_OUT INTS INTP AMS_GAIN AMS_IN AMS_LF VCO PEAK TBLANK TRIGGER OUT VR VSB HCL HCR VHCC AGND DIGGND 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 D94AU182 THERMAL DATA Symbol Rth j-pins 2/29 Parameter Thermal Resistance Junction-pins Value Unit max 85 °C/W COMPOSIT AM_L AM_C AM_R R1 L1 CD_L- CD_L+ CD_R+ CD_R- EQRI INR2 INR1 EQSW INL1 INL2 EQLI GND_PRE 61 60 59 58 57 56 54 50K 55 52 50K 53 48 47 46 39 44 43 42 45 100K 25K 25K 25K 25K 100K 20K 20K 3.8K (Nom) 5% step 41 51 25K 25K 0dB 25K 20K 20K 0dB 49 EQLO EQRO V CC_PRE RM RM L1 RADIO MUTE COMP MULTIPLEXER + MUTE R L 0 ÷ 15dB 1dB step G VCC 14 MUTE 0/-20dB/ -23dB/ MUTE 0/-20dB/ -23dB/ MUTE 0÷-6dB 0.5dB 50 0÷-6dB 0.5dB R1 PREOUT_R 40 PREOUT_L 18 + AMS_LF 28 AC_OUT1L FM/AM AGND 62 SUPPLY GAIN AC_OUT1R 2 29 AMS_IN CREF 1.5 ÷ 9dB 2.5dB GAIN 0÷28dB 1dB 3 AC_IN1_L 64 AC_IN1_R 1 AMS_GAIN AMS 30 32 INTS VS 33 27 456KHz BASS1_R 13 VOLUME +16 ÷ -63 1dB + MUTE (IN, OUT) 11 BASS1_L 19KHz CANCELLATION BUS LATCHES 100KΩ VCO PLL DEMODULATOR & AMPLITUDE ADJ 31 INTP VCC AMS OUT DOLBY B/C BASS2_L 12 BASS2_R 4 TR_L 5 AC_OUT2_R 6 7 AC_OUT2_L 26 9 AC_IN2_R CS4 63 PEAK 25 14 - November - 1995 TBLANK PEAK DETECTOR + PULSE FORMER LEVEL CONTROL HIGH CUT CONTROL 0 ÷ -79 1dB 0 ÷ -79 1dB 0 ÷ -79 1dB 0 ÷ -79 1dB 50 - 75 µsec DEEMPH I2 C BUS DECODER SOFT MUTE & RADIO MUTE 8 AC_IN2_L NOISE BLANKER THRESHOLD CONTROL TR_R RECTIFIER 25KHz BASS -18 ÷ +18 1dB TREBLE -18 ÷ +18 1dB 10 D94AU106I -5dB 24 22 19 23 20 21 17 15 16 38 34 35 36 37 TRIGGER_ OUT VSB VHCC VR HCR HCL DIG GND SDA SCL BEEP RF_OUT RR_OUT LF_OUT LR_OUT TDA7420 BLOCK DIAGRAM 3/29 100K TDA7420 ELECTRICAL CHARACTERISTICS (VS = 8.5V; Tamb = 25°C; RL = 10KΩ; all gains = 0dB; f = 1KHz; unless otherwise specified, refer to the Test Circuit.) Symbol Parameter Test Condition Min. Typ. Max. 63 Unit INPUT SECTION Differential Input Pins 52, 53, 54, 55 RI VCL CMRR GDIFF Input Resistance 37 50 2.0 2.5 Common Mode Rejection Ratio 45 55 Differential Gain -1 0 1 Input Resistance 75 100 125 Clipping Level 2.0 2.5 Clipping Level THD = 0.3% KΩ Vrms dB dB Stereo Input Pins 56, 57 RI VCL KΩ Vrms Quasi Differential Input Pins 58, 59,60 RI VCL Input Resistance 18 25 Clipping Level 2.0 2.5 32 KΩ Input Resistance 18 25 Clipping Level 2.0 2.5 100 200 300 -1 0 1 Ω dB Vrms Composite Input Pin 61 RI VCL 32 KΩ Vrms MULTIPLEXER RO Output Resistance (pin 2,3) GIMIN Minimum Gain GIMAX Maximum Gain 14 15 16 dB GSTEP Step Resolution 0.5 1 1.5 dB 1 5 VDC Dc Steps Adjacent Gain Step -5 GMIN to GMAX 2 mV mV VOLUME CONTROL RI Input Resistance (1, 64) 24 33 42 KΩ C MAX Max Gain 15 16 17 dB AMAX Max Attenuation dB 63 dB Step Resolution Coarse Attenuation AV = 16 to -40dB 0.5 1.0 1.5 EA Attenuation Set Error G =16 to -40dB -1.5 0 1.5 dB ET Tracking Error 2 dB VDC DC Steps 0.1 3 mV 0.5 5 mV ASTEPC Adjacent Attenuation Steps -3 from 0dB to AMAX SOFT MUTE AMUTE tD Mute Attenuation Delay Time 40 C EXT = 22nF; 0 to -20dB; I = IMAX I = I MIN 50 dB 1.0 ms 23 ms BASS CONTROL C RANGE ASTEP RB 4/29 Control Range +15 +18 +20 Step Resolution 0.5 1 1.5 dB dB Internal Feedback Resistance 48 65 82 KΩ TDA7420 ELECTRICAL CHARACTERISTICS (continued.) Symbol Parameter Test Condition Min. Typ. Max. Unit Control Range Step Resolution +17 0.5 +18 1 +19 1.5 dB dB Internal Feedback Resistance 37 50 63 KΩ 0.5 80 79 1 100 1.5 TREBLE CONTROL C RANGE ASTEP RT SPEAKER ATTENUATORS C RANGE ASTEP AMUTE EA VDC Control Range Step Resolution Output Mute Attenuation Attenuation Set Error DC Step AV = 0 to -40dB AV = 0 to -40dB Adjacent Attenuation Steps 0.1 1.50 3 dB dB dB dB mV 300 3.85 VRMS KΩ Ω V AUDIO OUTPUTS VCLIP RL ROUT VDC Clipping Level Output Load Resistance Output Impedance DC Voltage Level d = 0.3% Output Noise BW = 20Hz to 20KHz, flat Output Muted All gains = 0dB All gains 0dB; VO = 1VRMS ; VI = 1VRMS ; 2.0 2 100 3.35 2.5 200 3.6 GENERAL ENO S/N d SC ET Signal to Noise Ratio Distortion Channel Separation Left/Right Total Tracking Error 80 AV = 0 to -20dB; AV = -20 to -40dB; 4.0 5.0 106 0.01 95 0 0 15 0.08 1 2 µV µV dB % dB dB dB BUS INPUT V IL VIH IIN VO Input Low Voltage Input High Voltage Input Current Output Voltage SDA Acknowledge 1 VIN = 0.4V IO = 1.6mA 3 -5 0.1 5 0.4 V V µA V SUPPLY V IL IS Supply Voltage Supply Current SVR Ripple Rejection Cref = 22µF Stereo Decoder = ON Stereo Decoder = OFF Audioprocessor Stereo Decoder + Audioprocessor 6.5 25 20 8.5 33 28 80 60 10.0 41 35 V mA mA dB dB 5/29 TDA7420 PREAMPLIFIER (VS = 8.5V; T amb = 25°C; RIN = 600Ω; unless otherwise specified (see test circuit) Symbol RI Vout DC RO II Parameter Input Resistance Output Voltage DC (pin 40, 50) Output Resistance (pins 40, 50) Input Bias Current GVO GV Open Loop Gain Closed Loop Gain RN RMLR Resistance Normal Position Resistance Metal Position (left ,right) Step Resolution (versus RM) Maximum Value for RM Minimum Value for RM Dolby Level Control RMR RMmax R Mmin SR eN Slew Rate Total Input Noise Output Attenuation Control THD Total Harmonic Distortion Test Condition f = 400Hz NAB short Min. 100 3.2 100 Typ. Max. 3.5 200 3.9 300 10 31 110 32.5 34 µA dB dB 50 2.85 250 3.8 500 4.75 Ω KΩ 3.42 2.28 5.5 0.25 4.56 3.04 6.0 0.5 1 0.8 0.5 5.7 3.8 6.5 0.75 KΩ KΩ dB dB V/µs µV 5 Control Range Step Resolution NAB Short RIN = 600Ω; unweighted RIN = 600Ω; CCIR warn RIN = 0; unweighted D1, D0 = 00 D1, D0 = 01 D1, D0 = 10 D1, D0 = 11 VO = 1V; f = 1KHz metal VO = 1V; f = 1KHz normal VO = 1V; f = 10KHz metal VO = 1V; f = 10KHz normal -0.75 0.45 0 -20 -23 -80 0.02 0.02 0.05 0.04 % 0.75 0.1 VO = 2V; f = 1KHz SVR 1 CS CCT S/N Ripple Rejection Channel Separation (L to R) Channel Cross talk (F to R) Signal to Noise Unit KΩ V Ω µV µV dB dB dB dB % % % % % dB dB dB dB VO = 388mV; metal; CCIR arm 75 60 80 65 IAMOUT = 2mA 500 5 800 mA mV 100 1.45 5.2 2.8 0.2 0.2 70 125 1.7 5.6 3.6 0.8 0.8 150 KΩ V V V mV mV 70 11 42 17.5 22 100 150 45 60 AUDIO MUSIC SENSOR IAMSOUT VAMSOUT R i -29 VTH1 VTH2 AMS th VINTP VINTS 6/29 AMS Output Current AMS Output Low Level Input Resistance AMS Gain Interprogram Threshold Voltage Interspace Threshold Voltage AMS Threshold Level INTP Output Voltage INTS Output Voltage INTP Charge Current SG INTS Charge Current Gain Sensitivity R i - 30 AMS Gain Resistance (pin 23) 75 1.2 4.8 2.0 IOUT = 2mA IOUT = 2mA 50 50 min Gain V30 vs V29 max Gain V30 vs V29 D6, D5 = 00 D6, D5 = 01 D6, D5 = 11 13 16.5 75 22 27.5 125 µA µA dB dB KΩ KΩ KΩ TDA7420 STEREO DECODER PART ELECTRICAL CHARACTERISTICS (VS = 8.5V; de-emphasis time: T = 50µs; nominal MPX input voltage on pin 61 (composite): VMPX = 0.5VRMS (75KHz deviation); modulation frequency = 1KHz; GI = 1.5dB; Tamb = 27°C; unless otherwise specified) Symbol Parameter SVRR Supply Voltage Ripple Rejection VO DC Output Voltage (HCL, HCR) α Channel Separation THD S+N N Test Condition VRIPPLE = 100mV; f = 1KHz Min. 50 65 3.95 4.25 VSB - VR = 100mVDC Max. 0.02 f = 20Hz to 16KHz; S = 2VRMS Unit dB 4.55 50 Total Harmonic Distortion Signal Plus Noise to Noise Ratio Typ. V dB 0.3 91 % dB MONO/ STEREO SWITCH VINTH Pilot Threshold Voltage for stereo ”ON” P th = 1 P th = 0 12 19 16 26 22 34 mVRMS mVRMS VINTH Pilot Threshold Voltage for stereo ”OFF” P th = 1 P th = 0 8 16 14 22 20 28 mVRMS mVRMS -300 -250 -200 STEREO BLEND VSB-VR Control Voltage for Channel Separation α = 6dB; (note 5) α = 26dB; -80 mV mV HIGH CUT CONTROL τdeemp R HCC De-Emphasis Time Constant High Cut Control Resistance CL, C R = 1nF; STDDS = 0 VHCC - VR = 100mV 43 50 57 µs CL, C R = 1nF; STDDS = 1 VHCC - VR = 100mV 64 75 86 µs VHCC - VR = 100mV; STDDS = 0 43 50 57 KΩ VHCC - VR = -0.5V (note 5) 115 150 185 KΩ VCO fOSC Oscillator Frequency ∆f/f Capture and Hold Range 0.5 456 KHz 1 % CARRIER AND HARMONIC SUPPRESSION AT THE OUTPUT α19 Pilot Signal f = 19KHz 55 dB α38 Subcarrier f = 38KHz 75 dB α57 Subcarrier f = 57KHz 62 dB α76 Subcarrier f = 76KHz 90 dB 40 INTERMODULATION (note 1) α2 fmod = 10KHz; fspur = 1KHz 65 dB α3 fmod = 13KHz; fspur = 1KHz 75 dB 70 dB 75 dB TRAFFIC RADIO (note 2) α57 Signal f = 57KHz SCA - SUBSIDIARY COMMUNICATIONS AUTHORIZATION (note 3) α67 Signal f = 67KHz ACI - ADJACENT CHANNEL INTERFERENCE (note4) α114 Signal f = 114KHz 95 dB α190 Signal f = 190KHz 84 dB 7/29 TDA7420 NOTES TO THE CHARACTERISTICS 1 INTERMODULATION SUPPRESSION α2 = VO (signal) (at1KHz) ; fs = (2 x 10KHz) - 19KHz VO (spurious) (at1KHZ) α3 = VO (signal) (at1KHz) ; fs = (3 x 13KHz) - 38KHz VO (spurious) (at1KHZ) measured with : 91% mono signal; 9% pilot signal; fm=10KHz or 13KHz. 2. TRAFFIC RADIO (V.F.) suppression α57 (V.W.F.) = VO VO(signal) (at1KHz) (spurious) (at1KHZ ±23Hz) measured with : 91% stereo signal; 9% pilot signal; fm=1KHz; 5% subcarrier (f=57KHz, fm = 23Hz AM, m = 60%) 3. SCA (SUBSIDIARY COMMUNICATIONS AUTHORIZATION) α67 = VO(signal) (at1KHz) ; fs = (2 x 38KHz) - 67KHz VO (spurious) (at9KHZ) measured with : 81% mono signal; 9% pilot signal; fm=1KHz; 10% SCA - subcarrier (fs = 67KHz, unmodulated). 4. ACI (ADJACENT CHANNEL INTERFERENCE) α114 = VO(signal) (at1KHz) ; fs = 110KHz - (3 x 38KHz) VO (spurious) (at4KHZ) α190 = VO(signal) (at1KHz) ; fs = 186KHz - (5 x 38KHz) VO (spurious) (at4KHZ) measured with 90% mono signal; 9% pilot signal; fm = 1KHz; 1% spurious signal (fs = 110KHz or 186KHz, unmodulated). 5: Control range for High Cut Control and Stereo Blend is VR - 400mV ≤ VSB, VHCC ≤VR Figure : High Cut Control Figure : Stereo Blend fc (KHz) D94AU183 SEP (dB) D94AU184 40 3 30 2 20 1 10 0 -500 8/29 -400 -300 -200 -100 0 VHCC-VR 0 -400 -300 -200 -100 VSB - VR TDA7420 ADDITIONAL CIRCUITS FOR DEVIATION AND FIELD STRENGTH -DEPENDENT TRIGGER ADJUSTMENT BLANKING TIME PROGRAMMABLE BY EXTERNAL CAPACITOR VERY LOW OFFSET CURRENT DURING HOLD TIME DUE TO OPAMPS WITH MOS INPUTS NOISE BLANKER PART FEATURES: INTERNAL 2nd ORDER 140KHz HIGH-PASS FILTER NOISE RECTIFIER OUTPUT FOR SIGNAL QUALITY DETECTION PROGRAMMABLE TRIGGER THRESHOLD TRIGGER THRESHOLD DEPENDENT ON HIGH FREQUENCY NOISE WITH PROGRAMMABLE GAIN ELECTRICAL CHARACTERISTICS (continued) Symbol VTRMIN VTRMIN VTRSTEP VTRNOISE VPEAK Parameter Test Condition Trigger Threshold (*) 1) minimum Trigger Threshold 1) maximum Measured with NBT = 000 VPEAK = 1.2V Measured with NBT = 111 VPEAK = 1.2V Min. Typ. Max. Unit D2 on byte 2 = 1 D2 on byte 2 = 0 100 150 30 200 mVp D2 on byte 2 = 1 D2 on byte 2 = 0 130 185 65 250 mVp Trigger Threshold Step Size Noise Adjusted Trigger Threshold Rectifier Voltage D2 on byte 2 = 1 2) Measured with VPEAK = 1.4V D2 on byte 2 = 0 NAT NAT NAT NAT = 00 = 01 = 10 = 11 5 mVp 140 180 240 280 mVp mVp mVp mVp VMPX = 0mV 0.9 V VMPX = 50mV f = 200KHz 1.5 V VMPX = 100mV f = 200KHz 2.0 V VRECTDEV Deviation Dependent Rectifier Voltage 3) Measured with VMPX = 500mV (75KHz dev.) OVD OVD OVD OVD = 00(off) = 01 = 10 = 11 0.9 1.2 2.0 2.8 V V V V VRECTFS Field Strength Controlled Rectifier Voltage 4) Measured with VMPX = 0mV VSB-VR = -500mV (fully mono.) FSC FSC FSC FSC = 00(off) = 01 = 10 = 11 0.9 1.3 1.9 2.4 V V V V TS Suppression Pulse Duration CBLANK = 330pF IOS Input Offset Current During Suppression Time 40 µs 10 pA (*) All thresholds are measured by using a pulse with T R = 2µs, THIGH = 2µs and TF = 10µs. The repetition rate must not increase the PEAK voltage. 1) NTB represents bits D0 - D2 of NB byte 1 2) NAT represents bits D3 - D4 of NB byte 1 VMPX 3) OVD represents bits D5 - D6 of NB byte 1 VTH 4) FSC represents bits D0 - D1 of NB byte 2 DC-LEVEL Time D94AU185 TR THIGH TF 9/29 TDA7420 DESCRIPTION DESCRIPTION OF THE NOISEBLANKER In the normal automotive environment the MPX signal is disturbed by ignition spikes, motors and high frequency switches etc. The aim of the noiseblanker part is to cancel the influence of the spikes produced by these components. Therefore the output of the stereodecoder is switched off for a time of 40µs (average spike duration). In a first stage the spikes must be detected but to avoid a wrong triggering on high frequency noise a complex trigger control is implemented. Behind the triggerstage a pulse former generates the 40µs ”blanking” pulse. In the following section all of these circuits are described in their function and their programming, too (see fig.1). 1.1 Normal Trigger Path (RECT-PEAK, ACT, PEAK-COMP, BLANK-COMP, BIAS-MONO) The Incoming MPX signal is highpass-filtered, amplified and rectified (block RECT-PEAK). The second order highpass-filter has a corner-frequency of 140KHz. The gain of the rectifier can be controlled by the bit D2 of the noiseblanker byte2. If programming bit D2 to zero the gain is only half of the nominal value. All trigger thresholds must be roughly doubled in this case. The rectified signal, RECT, is used to generate by peak-rectification a signal called PEAK, which is available at the PEAK pin. Also noise with a frequency >100KHz increases the PEAK voltage. The value of the PEAK voltage influences the trigger threshold voltage Vth (block ATC). Both signals, RECT and PEAK+Vth are fed to a comparator (block PEAK-COMP) which outputs a sawtooth-sharped waveform at the TBLANK pin, it is triggered. A second comparator (block BLANK-COMP) forms the internal blanking duration of 40µs. The noiseblanker is supplied by his own biasing circuit (block BIAS-MONO). 1.2 Automatic Threshold Control (ATC) There are two independent possibilities for programming the trigger threshold: a)the minimum threshold in 8 steps (bits D0-D2, 10/29 NB-byte 1) b)the maximum threshold in 4 steps (bits D3D4, NB-byte 1) (see fig.2) The low threshold is used in combination with a good MPX signal without any noise. The sensitivity in this operation is high, depending only on the programmed ”Low Trigger Threshold”, bits D0-D2 of the noiseblanker byte 1. It is independent of the PEAK voltage. The MPX signal is noisy (low fieldstrength) the PEAK signal increases due to the higher noise, which is also rectified (see part 1.1). With increasing of the PEAK voltage the trigger threshold voltage increases, too. This particular gain is programmable in 4 steps (see fig.2). 1.3 Automatic Threshold Control by the Stereoblend voltage (ATC-SB) Besides the noise controlled threshold adjustment there is an additional possibility for influencing the trigger. It is controlled by the difference between Vsb and Vr, similar to the Stereoblend. The reason for implementing such a second control will be explained in the following: 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 (fig.3). But in some cases the behaviour of the noiseblanker can be improved by increasing the threshold even in a region of higher fieldstrength, for the MPX signal often shows distortion in this range. Because of the overlap of this range and the range of the stereo/mono transition it can be controlled by Vsb and Vr. This threshold increase is programmable in 3 steps or switched off (see fig.3). 1.4 Over Deviation Detector (MPX-RECT) Sometimes when listening to stations with a higher deviation than 75KHz the noiseblanker triggers on the high frequency modulation. To avoid this blanking, which causes noise in the output signal, the noiseblanker offers a deviationdependent 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 (the first step turns off the detector, see fig.4). TDA7420 Figure 1: Block Diagram of the Noise Blanker LEFT 80KHz LP SIGNAL PATH RIGHT BLANK COMP PEAK COMP RECT AMP MPX IN BUF PEAK + to INPUT SELECTOR of AUDIOPROC. REF. TRIGGER OUT - AUTOMATIC THRESHOLD CONTROL ATC PEAK+VTH CMOS OUTPUT STAGE 40µs 40µs 5 RECT-PEAK 1 4 I2C-BUS ADDITIONAL THRESHOLD CONTROL (ATC-SB, MPX_RECT) VR VSB RPEAK 82KΩ CPEAK 47nF CBLANK 330pF D94AU189A Figure 2: Trigger Threshold vs. Vpeak VTH 280mV 240mV 180mV 140mV NOISE ADJUSTED TRIG. THRESHOLD TRIG. THRESHOLD 65mV 8 STEPS 30mV 0.9V D94AU186B 1.4V VPEAK(V) 11/29 TDA7420 Figure 3: Behaviour of the Field Strength Controlled Threshold Adjustment VPEAK MONO STEREO 3G 2.4V(11) 1.9V(10) 1.3V(01) TRIG. THRESHOLD NOISE 0.9V ATC_SB OFF (00) noisy signal good signal D94AU187B E’ Figure 4: Behaviour of the Deviation Dependent Threshold Adjust (Over Deviation Detector) VPEAK (V) OVM=11 OVM=10 2.8 2.0 OVM=01 1.2 0.9 DETECTOR OFF (00) D94AU188 20 32.5 45 I2C BUS INTERFACE Interface Protocol The interface protocol comprises: A start condition (s) A chip address byte, (the LSB bit determines read/write transmission). CHIP ADDRESS MSB S 1 0 0 1 0 A subaddress byte A sequence of data (N-bytes + acknowledge) A stop condition (P) DATA 1...DATA n SUB ADDRESS LSB 0 DEVIATION(KHz) 75 LSB MSB 0 R/W ACK X X T I MSB A3 A2 A1 A0 ACK LSB DATA ACK = Acknowledge S = Start P = Stop I = Autoincrement MAX CLOCK SPEED 500kbits/s Autoincrement If bit I in the subaddress byte is set to ”1”, the autoincrement of subaddress is enabled. 12/29 ACK P TDA7420 TRANSMITTED DATA (SEND MODE) MSB LSB X X X X X ST SM AMS HIGH = Active AMS = True Blank Detected SM = Soft mute activated ST = Stereo (HIGH = active) SUBADDRESS (RECEIVE MODE) MSB X LSB X X I FUNCTION D3 D2 D1 D0 0 0 0 0 Mux 0 0 0 1 Volume 0 0 1 0 Treble 0 0 1 1 Bass 0 1 0 0 Speaker Attenuator LF 0 1 0 1 Speaker Attenuator RF 0 1 1 0 Speaker Attenuator LR 0 1 1 1 Speaker Attenuator RR 1 0 0 0 Mute & Beep 1 0 0 1 Stereodecoder 1 0 1 0 Noise Blanker 1 1 0 1 1 Noise Blanker 2 1 1 0 0 AMS 1 1 0 1 Dolby Level Control 1 1 1 0 Metal Resistance Control 1 1 1 1 Preamplifier Attenuation If bit in the subaddress byte is set to ” 1”, the autoincrement of subaddress is enabled 13/29 TDA7420 INPUT SELECTOR MSB D7 D6 D5 D4 D3 D2 D1 LSB D0 0 0 0 0 0dB 0 0 0 1 1dB 0 0 0 0 1 1 0 1 2dB 3dB 0 0 1 1 0 0 0 1 4dB 5dB 0 1 1 0 6dB 0 1 1 1 7dB 1 1 0 0 0 0 0 1 8dB 9dB 1 1 0 0 1 1 0 1 10dB 11dB 1 1 0 0 12dB 1 1 0 1 13dB 1 1 1 1 1 1 0 1 14dB 15dB FUNCTION Input Gain 14/29 0 0 0 Full diff CD 0 0 1 Stereo 0 0 1 1 0 1 Stereo Decoder AM quasi diff input 1 1 0 0 0 1 Quasi diff CD Not allowed 1 1 0 Not allowed 1 1 1 AM Mono (AM R input) TDA7420 VOLUME MSB D7 LSB D6 D5 D4 D3 FUNCTION D2 D1 D0 0 0 0 -0dB 0 0 1 -1dB 0 1 0 -2dB 0 1 1 -3dB 1 0 0 -4dB 1 0 1 -5dB 1 1 0 -6dB 1 1 1 -1 dB STEPS -7dB -8 dB STEPS 0 0 1 0 0 0 16dB 0 0 1 8dB 0 1 0 0dB 0 1 1 -8dB 1 0 0 -16dB 1 0 1 -24dB 1 1 0 -32dB 1 1 1 -40dB 1 0 0 0 -48dB 1 0 0 1 -56dB Mute 15/29 TDA7420 TREBLE MSB D7 16/29 LSB D6 FUNCTION D5 D4 D3 D2 D1 D0 1 1 0 0 1 0 -18dB 1 1 0 0 0 1 -17dB 1 1 0 0 0 0 -16dB 1 0 1 1 1 1 -15dB 1 0 1 1 1 0 -14dB 1 0 1 1 0 1 -13dB 1 0 1 1 0 0 -12dB 1 0 1 0 1 1 -11dB 1 0 1 0 1 0 -10dB 1 0 1 0 0 1 -9dB 1 0 1 0 0 0 -8dB 1 0 0 1 1 1 -7dB 1 0 0 1 1 0 -6dB 1 0 0 1 0 1 -5dB 1 0 0 1 0 0 -4dB 1 0 0 0 1 1 -3dB 1 0 0 0 1 0 -2dB 1 0 0 0 0 1 -1dB 1 0 0 0 0 0 0dB 0 0 0 0 0 0 0dB 0 0 0 0 0 1 1dB 0 0 0 0 1 0 2dB 0 0 0 0 1 1 3dB 0 0 0 1 0 0 4dB 0 0 0 1 0 1 5dB 0 0 0 1 1 0 6dB 0 0 0 1 1 1 7dB 0 0 1 0 0 0 8dB 0 0 1 0 0 1 9dB 0 0 1 0 1 0 10dB 0 0 1 0 1 1 11dB 0 0 1 1 0 0 12dB 0 0 1 1 0 1 13dB 0 0 1 1 1 0 14dB 0 0 1 1 1 1 15dB 0 1 0 0 0 0 16dB 0 1 0 0 0 1 17dB 0 1 0 0 1 0 18dB TDA7420 BASS MSB D7 LSB D6 FUNCTION D5 D4 D3 D2 D1 D0 1 1 0 0 1 0 -18dB 1 1 0 0 0 1 -17dB 1 1 0 0 0 0 -16dB 1 0 1 1 1 1 -15dB 1 0 1 1 1 0 -14dB 1 0 1 1 0 1 -13dB 1 0 1 1 0 0 -12dB 1 0 1 0 1 1 -11dB 1 0 1 0 1 0 -10dB 1 0 1 0 0 1 -9dB 1 0 1 0 0 0 -8dB 1 0 0 1 1 1 -7dB 1 0 0 1 1 0 -6dB 1 0 0 1 0 1 -5dB 1 0 0 1 0 0 -4dB 1 0 0 0 1 1 -3dB 1 0 0 0 1 0 -2dB 1 0 0 0 0 1 -1dB 1 0 0 0 0 0 0dB 0 0 0 0 0 0 0dB 0 0 0 0 0 1 1dB 0 0 0 0 1 0 2dB 0 0 0 0 1 1 3dB 0 0 0 1 0 0 4dB 0 0 0 1 0 1 5dB 0 0 0 1 1 0 6dB 0 0 0 1 1 1 7dB 0 0 1 0 0 0 8dB 0 0 1 0 0 1 9dB 0 0 1 0 1 0 10dB 0 0 1 0 1 1 11dB 0 0 1 1 0 0 12dB 0 0 1 1 0 1 13dB 0 0 1 1 1 0 14dB 0 0 1 1 1 1 15dB 0 1 0 0 0 0 16dB 0 1 0 0 0 1 17dB 0 1 0 0 1 0 18dB 1 Non DC extended bass 0 DC extended bass 17/29 TDA7420 SPEAKERS ATTENUATORS MSB D7 LSB D6 D5 D4 D3 LF, LR, RF, RR D2 D1 D0 0 0 0 0dB 0 0 1 -1dB 0 1 0 -2dB 0 1 1 -3dB 1 0 0 -4B 1 0 1 -5dB 1 1 0 -6dB 1 1 1 -7dB -1dB STEPS 8dB STEPS 0 0 0 0 0dB 0 0 0 1 -8dB 0 0 1 0 -16dB 0 0 1 1 -24dB 0 1 0 0 -32dB 0 1 0 1 -40dB 0 1 1 0 -48dB 0 1 1 1 -56dB 1 0 0 0 -64dB 1 0 0 1 -72dB 1 1 0 1 0 1 1 1 1 D5 D4 Mute MUTE & BEEP MSB D7 LSB D6 1 1 D3 D2 D1 FUNCTION D0 1 Soft Mute - FAST SLOPE 0 Soft Mute - Slow Slope 1 Soft Mute OFF 0 Soft Mute ON 0 0 Direct Input Mute ON 1 0 Direct Input Mute OFF 0 0 Radio Mute ON 1 0 Radio Mute OFF 1 Composit Input Enabled 0 Composit Mute Enabled Beep ON - Front Beep ON - Rear 1 VCO OFF 0 VCO ON 18/29 TDA7420 STEREO DECODER MSB D7 LSB D6 D5 D4 D3 D2 FUNCTION D1 D0 0 0 1.5dB Input Gain 0 1 4.0dB Input Gain 1 0 6.5dB Input Gain 1 1 Input Gain 9dB Input Gain Roll Off Adjustement 0 0 1 20.2% 0 1 0 21.9% 0 1 1 23.7% 1 0 0 25.5% 1 0 1 27.3% 1 1 0 29.2% 1 1 1 31% 0 Deemph. Time Constant 75µs 1 Deemph. Time Constant 50µs 1 Forced Mono 0 Stereo Enabled 0 Pilot Threshold High 1 Pilot Threshold Low NOISE BLANKER 1 MSB D7 LSB D6 D5 D4 D3 D2 D1 FUNCTION D0 Noise Blanker Threshold Vpeak = 0.9V 0 0 0 Vth = 30mV 0 0 1 Vth = 35mV 0 1 0 Vth = 40mV 0 1 1 Vth = 45mV 1 0 0 Vth = 50mV 1 0 1 Vth = 55mV 1 1 0 Vth = 60mV 1 1 1 Vth = 65mV Noise Blanker Noise Adjusted Threshold Vpeak = 1.4V 0 0 Vth = 140mV 0 1 Vth = 180mV 1 0 Vth = 240mV 1 1 Vth = 280mV Gain of Overdeviation Detector Vpeak with MPX of 75KHz Deviation 0 0 Detector Off 0 1 Vpeak = 1.2Vop 1 0 Vpeak = 2.0Vop 1 1 Vpeak = 2.8Vop 19/29 TDA7420 NOISE BLANKER 2 MSB D7 LSB D6 D5 D4 D3 D2 D1 FUNCTION D0 Field Strenght Controlled Rectifier Voltage (control by Vsb-Vr) Vpeak at Vsb-Vr = -500mV (fully Mono) 0 0 Control Off 0 1 Vpeak = 1.3V 1 0 Vpeak = 1.9V 1 1 Vpeak = 2.4V Noise Blanker Gain 1 Low 0 High AMS MSB D7 LSB D6 D5 D4 D3 D2 FUNCTION D1 D0 0 0 0dB 0 1 -1dB 1 1 0 1 -2dB -3dB Gain Sensitivity Tuning Att. Sensitivity Tuning 0 1 20/29 0 0 0 0dB 0 0 1 10dB 0 0 1 1 0 1 14dB 18dB 1 1 0 0 0 1 22dB 26dB 1 1 0 30dB 1 1 1 34dB 0 0 0 1 AC Sensitivity Tuning 22dB f = 1.1KHz SW1 = SW2 = SW3 34dB f = 1.1KHz 1 0 not allowed 1 1 21dB f = 160Hz AMS ON AMS OFF TDA7420 DOLBY LEVEL CONTROL MSB D7 LSB D6 D5 D4 FUNCTION D3 D2 D1 D0 0 0 0 0 0dB 0 0 0 1 -0.5dB 0 0 1 0 -1.0dB 0 0 1 1 -1.5dB 0 1 0 0 -2.0dB 0 1 0 1 -2.5dB 0 1 1 0 -3.0dB 0 1 1 1 -3.5dB 1 0 0 0 -4.0dB 1 0 0 1 -4.5dB 1 0 1 0 -5.0dB 1 0 1 1 -5.5dB 1 1 X X -6.0dB Right Channel Left Channel 0 0 0 0 -0dB 0 0 0 1 -0.5dB 0 0 1 0 -1.0dB 0 0 1 1 -1.5dB 0 1 0 0 -2.0dB 0 1 0 1 -2.5dB 0 1 1 0 -3.0dB 0 1 1 1 -3.5dB 1 0 0 0 -4.0dB 1 0 0 1 -4.5dB 1 0 1 0 -5.0dB 1 0 1 1 -5.5dB 1 1 X X -6.0dB 21/29 TDA7420 METAL RESISTANCE CONTROL MSB D7 LSB D6 D5 D4 FUNCTION D3 D2 D1 D0 1 0 0 0 R metal +20% 0 0 0 0 R metal +15% 0 0 0 1 R metal +10% 0 0 1 0 R metal +5% 0 0 1 1 R metal =3.8KΩ Typical 0 1 0 0 R metal - 5% 0 1 0 1 R metal - 10% 0 1 1 0 R metal - 15% 0 1 1 1 Right Channel R metal - 20% Left Channel 1 0 0 0 R metal +20% 0 0 0 0 R metal +15% 0 0 0 1 R metal +10% 0 0 1 0 R metal +5% 0 0 1 1 R metal =3.8KΩ Typical 0 1 0 0 R metal - 5% 0 1 0 1 R metal - 10% 0 1 1 0 R metal - 15% 0 1 1 1 R metal - 20% D5 D4 PREAMPLIFIER MSB D7 LSB D6 D3 D2 FUNCTION D1 D0 0 0 0dB 0 1 -20dB 1 0 -23dB 1 1 Mute Attenuation control 22/29 0 Reverse Mode On 1 Forward Mode On TDA7420 PINS: 1, 64 PINS: 2, 3,6,7, VCC V CC VCC 20µA 20µA GND GND 33K 50K GND Vcc/2 D95AU267 D95AU268 VCC/2 PINS: 40, 50 VCC PINS: 8, 9 VCC V CC 20µA 20µA 205 33K GND GND D95AU270 D95AU269 PINS: 10, 12 Vcc/2 GND PINS: 11, 13 VCC VS 20µA 20µA GND GND 65K 65K BASS-LB PIN 11 PIN 13 D95AU271A BASS-RB D95AU272 23/29 TDA7420 PIN: 15 PIN: 16 20µA 20µA GND GND D95AU273 GND PIN: 19 D95AU274 PINS: 20, 21 20µA VCC VCC 40µA 205 VCC GND VCC 4K GND 25K 75K GND D95AU275 GND GND D95AU276 GND PIN: 22 PIN: 23 20µA VCC 40µA VCC 20µA 205 40µA GND GND 16K 205 VCC GND D95AU277 24/29 GND D95AU278 GND TDA7420 PIN: 24 PIN: 25 VCC VCC VCC 35µA 40µA 205 205 GND GND GND D95AU279 GND D95AU280 PIN: 27 PIN: 26 VCC VCC VCC VCC V CC V CC 4K 40µA 6K 280 50µA 2K 100µA 500 GND GND 500 GND 56K D95AU282 D95AU281 PIN: 28 PINS: 29, 56, 57 VCC VCC 20µA VCC 12K 20µA GND GND VCC 20µA 100K 12K GND GND VCC/2 D95AU284 D95AU283 25/29 TDA7420 PIN: 30 PIN: 31 VCC VCC VCC 10K GND 100K GND GND GND GND D95AU286 D95AU285 PIN: 33 PIN: 32 VCC VCC VCC 29K GND GND GND GND GND GND PINS: 34, 35, 36, 37 GND D95AU288 D95AU287 PINS: 38 VCC VCC 205 20µA 24 50K GND GND 20µA 50K GND D95AU289 26/29 GND VCC/2 D95AU290 TDA7420 PINS: 39 PINS: 41,49 VCC VCC VCC VCC 4.56K 205 224K GND GND GND GND D95AU291 D95AU292 PINS: 42, 48 PINS: 43, 44, 46, 47 VCC VCC 20µA 205 GND GND GND D95AU293 PIN 43, 44 D95AU294 PIN 46, 47 PINS: 52, 53 PINS: 54, 55 VCC VCC 50K GND 50K GND PIN 52 VCC/2 20K 20µA 20K PIN 54 20K VCC/2 PIN 55 20K PIN 53 D95AU295 D95AU296 27/29 TDA7420 PIN: 59 PINS: 58, 60 VCC VCC 20µA VCC 20µA 25K 25K 25K VCC/2 20µA GND GND 25K GND D95AU297 PIN: 61 D95AU298 PIN: 62 VCC VCC VCC 20µA 20K 20K 25K GND VCC/2 D95AU299 PIN: 63 VCC 20µA 10K 1.7K GND GND D95AU301 28/29 GND GND GND GND D95AU300 TDA7420 Information furnished is believed to be accurate and reliable. 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