TDA7476 STMicroelectronics, TDA7476 Datasheet
TDA7476
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TDA7476 Summary of contents
Page 1
... GND 1 24 SDA 2 23 SCL 3 22 ADD AUX1 OUT 6 19 AUX1 AUX2 AUX2 OUT ST- D97AU570A TDA7476 MULTIPOWER BCD TECHNOLOGY SO-24 ORDERING NUMBER: TDA7476 CH5- CH5+ CH4+ CH4- CH3- CH3+ CH2+ CH2- CH1- CH1+ T-CAP CSR 1/19 ...
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... TDA7476 BLOCK DIAGRAM & APPLICATION CIRCUIT SDA SCL ADD 100nF R3 W 10K R4 10K ST-BY SW1 5V REF DIG-GND PIN FUNCTION N° Pin 1 GND Ground 2 SDA Dta line 3 SCL Clock line 4 ADD Address select 5 W Warning 6 AUX1 OUT AUX1 output 7 AUX1 IN AUX1 input ...
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... Audio Output is considered in Short Circuit to Vs) Pnop Normal operation thresholds. (Within these limits, the Audio Output is considered without faults) Parameter Parameter Max. Test Condition Stand-By Voltage Pin = 1.5V Total quiescent Current with TDA7476 not addressed Power amplifier in st-by condition TDA7476 Value Unit 1.5 W -40 to 150 ° ...
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... TDA7476 ELECTRICAL CHARACTERISTICS (continued 14.4V 25°, unless otherwise specified.) s amb Symbol Parameter Lsc Shorted Load det. (voltage across the Audio Outputs). Below this limit the load is considered shorted. Lop Open Load det. (voltage across the Audio Outputs). Above this limit the load is considered open. ...
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... Test Condition High side driver ON Sink Current at Pin 5 = 1mA Address 0100010X Address 0100011X Sink Current at Pin 2 = 5mA Figure 1. I(mA) I SOURCE I SINK t m TDA7476 Min. Typ. Max. Unit 0.085 V 0.125 0 1 ...
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... TDA7476 Isink and Isource are depending on the external resistor Rcs. The minimum allowed value for Rcs is 1.65KOhm. The relationship among Isink, Isource and Rcs is the following: On bridge (or bridge equivalent) devices if there is no short circuit to GND or to Vs, Isource goes into saturation mode (for Vout > 3V), and in the load flows Isink. As the turn-on diagnostic thresholds are fixed possible to calculate the ranges of loudspeaker resistance in which short circuit (S ...
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... If one or more outputs stay at any voltage below 0.8V or over Vs-0.6V for more than 2 sec. (typ), the warning pin is pulled down.The P can address the TDA7476 to know the status.The subsonic current pulse is activated also in this case. The fault is correctly detected if it remains until the memorization (tm in fig.1).In this phase, faults regarding shorts across the load and open loads cannot be detected ...
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... Note: some faults can mask others if they are present at the same moment on the same channel there is a short to GND and an open load on the same channel, the TDA7476 gives information only about one of them, depending on the wire on which the short circuit is present. ...
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... The following table shows the result pointed out by TDA7476 when multiple misconnections are present: ACTUAL FAULTS S.C. CH+ to GND + OPEN LOAD S.C. CH(*) to GND + S.C. ACROSS LOAD S.C. CH- to GND + OPEN LOAD S.C. CH(*) OPEN LOAD S S.C. CH(*) S.C. ACROSS LOAD S S.C. CH S.C. CH- to GND S S ...
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... I C BUS INTERFACE Data transmission from microprocessor to the TDA7476 and viceversa takes place through the 2 wires I interface, consisting of the two lines SDA and SCL (pull-up resistors to positive supply voltage must be connected). Data Validity As shown by fig. 2, the data on the SDA line must be stable during the high period of the clock. The HIGH and LOW state of the data line can only change when the clock signal on the SCL line is LOW ...
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... S 010001A 0 The byte ADD2 contains the bit level. This enables the reading mode, TDA7476's. The 3 bytes with the diagnostic information BYTE1, BYTE2, BYTE3 (READ FROM TDA7476) are now transmitted to the P. The address of TDA7476 is selected using pin ADD (pin ADD is connected to ground, then and the TDA7476 address is 0100010X. ...
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... In this case the above conditions are not detected while the single infrasonic current pulse is present but be- fore. The fault condition must be present for more than 2sec. (typ) and must be also true during the pulse, where the data are memorized and then transmitted.The bytes from/to P and TDA7476 are the same as those in case of turn-on diagnostic (see above). ...
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... ADD1, it does the permanent diagnostic. This is not true if, when the P sends for the first time the byte ADD2, it does not send to the TDA7476 the acknowledge after it has received the byte BYTE3. In this case, the TDA7476 does not switch from turn-on to permanent diagnostic mode receives again the byte ADD1 it works as it was the first time that it does the turn-on diagnostic ...
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... ADD2 ACK In this way only after that the TDA7476 has done for N times the turn-on diagnostic, it switches from turn-on to permanent diagnostic mode.From now the TDA7476 always does the permanent diagnostic.To save time when the audio system is switched on possible to do the repetitive turn-on diagnostic when the car-radio is turned off. In this case the steps to follow to do the repetitive turn-on diagnostic are the following switch off the TDA7476 connecting STBY pin to ground ...
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... CH1+ is shorted to ground, the TDA7476 reveals a short to ground both for CH2 and for CH1. - see fig.6 if CH1+ is shorted to ground, the TDA7476 detects a short circuit to ground for CH1, CH2, CH3, CH4. ...
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... TDA7476 To use the TDA7476 with a car-radio system which has less than five audio channel and less than two auxiliary loads necessary to take some cares: - each pin CH± not used has to be fixed each pin AUX1IN, AUX1OUT, AUXIN2, AUX2OUT not used has to be fixed to a voltage equal or greater than 5V The 5V voltage reference available on the chip (pin 10) is very useful to fix both CH± ...
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... TDA7375 CH1+ CH2+ CH3+ CH4+ CH5+ D97AU575A Figure 8. TDA7375 in S.E. mode with 2 output capacitors TDA7375 CH1+ CH2+ CH3+ CH4+ CH5+ D97AU576A + - - + + - - + R CH5- CH4- CH3- CH2- CH1- TDA7476 + - - + + - - + R CH5- CH4- CH3- CH2- CH1- TDA7476 TDA7476 C OUT1 C OUT2 C OUT3 C OUT4 C OUT1 C OUT2 17/19 ...
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... TDA7476 mm DIM. MIN. TYP. MAX. A 2.35 2.65 0.093 A1 0.10 0.30 0.004 A2 2.55 B 0.33 0.51 0.013 C 0.23 0.32 0.009 D 15.20 15.60 0.598 E 7.40 7.60 0.291 e 1.27 H 10.0 10.65 0.394 h 0.25 0.75 0.010 k 0 (min.), 8 (max.) L 0.40 1.27 0.016 B 0.10mm .004 Seating Plane ...
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... STMicroelectronics. The ST logo is a registered trademark of STMicroelectronics Australia - Brazil - China - Finland - France - Germany - Hong Kong - India - Italy - Japan - Malaysia - Malta - Morocco - Singapore - Spain 2001 STMicroelectronics - All Rights Reserved ® STMicroelectronics GROUP OF COMPANIES - Sweden - Switzerland - United Kingdom - U.S.A. http://www.st.com TDA7476 19/19 ...