E-TDA7476 STMicroelectronics

TDA7476 CAR RADIO DIAGNOSTIC PROCESSOR WIDE OPERATING VOLTAGE RANGE MULTIPOWER BCD TECHNOLOGY ST-BY FUNCTION (C-MOS) LOW QUIESCENT ST-BY CURRENT CONSUMPTION 2 I C BUS INTERFACE WITH 2 EXTERNALLY SELECTABLE ADDRESSES UP TO 5 BTL EQUIVALENT INPUTS FOR FAULT DETECTION IN THE AUDIO CHANNELS SO-24 - short to GND ORDERING NUMBER: TDA7476 - short to Vs - short across the load (at turn-on) - open load (at turn-on) 2 AUX INPUTS FOR FAULT DETECTION IN THE ANTENNA AND BOOSTERS SUPPLY DESCRIPTION LINE- short to GND- open load WARNING PIN FUNCTION (interrupt facility) The car radio diagnostic processor is an interface ACTIVATED IN THE FOLLOWING chip in BCD Technology intended for car radio appli- CONDITION: cations. It is able to detect potential faults coming - audio channel shorted to V S from any misconnection in the car radio or in the har- - audio channel shorted to GND ness when installing the set. - aux input shorted to GND NOISE FREE DIAGNOSTICS OPERATION The device is able to reveal any fault in the loud- PROTECTORS speaker lines and in the antenna and booster supply LOAD DUMP VOLTAGE lines, providing a proper output signal (I2C bus com- OPEN GND patible) in order to disable the ICs under fault and/or REVERSED BATTERY to alert the micro-controller by means of warning ESD messages. PIN CONNECTION (Top view) GND 1 24 CH5- SDA 2 23 CH5+ SCL 3 22 CH4+ ADD 4 21 CH4- W 5 20 CH3- AUX1 OUT 6 19 CH3+ AUX1 IN 7 18 CH2+ AUX2 IN 8 17 CH2- AUX2 OUT 9 16 CH1- 5V 10 15 CH1+ ST-BY 11 14 T-CAP V 12 13 CSR S D97AU570A April 2001 1/19 TDA7476 BLOCK DIAGRAM & APPLICATION CIRCUIT 2 24 SDA 3 23 CH5 2 SCL I C INTERFACE 4 ADD 22 21 CH4 V 12 S C3 C2 20 10F 100nF 19 CH3 R3 W 5 DELAY 18 10K 17 CH2 R4 CURRENT 10K FORCING 16 & 11 ST-BY COMPARATORS 15 CH1 10 SW1 VOLTAGE REGULATOR 6 14 OUT 5V & REF TEST SIGNAL GENERATOR 13 RSENS1 AUX1 7 C1 IN C R CS T 10F 8 IN RSENS2 AUX2 R5 51 DIG-GND19 OUT D96AU499A PIN FUNCTION N Pin Description 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 8 AUX2 IN AUX2 input 9 AUX2 OUT AUX2 output 10 5V 5V-Regulator 11 ST-BY Stand-by 12 V Supply Voltage S 13 CSR Current setting resistor 14 T-CAP Timing capacitor 15/16 CH1+/CH1- Audio output - Channel 1 17/18 CH2-/CH2+ Audio output - Channel 2 19/20 CH3+/CH3- Audio output - Channel 3 21/22 CH4-/CH4+ Audio output - Channel 4 23/24 CH5+/CH5- Audio output - Channel 5 2/19