TDA7476

CAR RADIO DIAGNOSTIC PROCESSOR

PRELIMINARY DATA

WIDE OPERATING VOLTAGE RANGE

ST-BY FUNCTION (C-MOS)

LOW QUIESCENT ST-BY CURRENT CON-

SUMPTION

I2C BUS INTERFACE WITH 2 EXTERNALLY

SELECTABLE ADDRESSES

UP TO 5 BTL EQUIVALENT INPUTS FOR

FAULT DETECTION IN THE AUDIO CHAN-

NELS

- short to GND

- 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

LINE

- short to GND

- open load

WARNING PIN FUNCTION (interrupt facility)

ACTIVATED IN THE FOLLOWING CONDI-

TION:

- audio channel shorted to GND

- aux input shorted to GND

NOISE FREE DIAGNOSTICS OPERATION

PROTETCTORS

LOAD DUMP VOLTAGE

OPEN GND

REVERSED BATTERY

ESD

DESCRIPTION

The car radio diagnostic processor is an interface

chip in BCD Technology intended for car radio

applications. It is able to detect potential faults

coming from any misconnection in the car radio or

in the harness when installing the set.

The device is able to reveal any fault in the loud-

speaker lines and in the antenna and booster

supply lines, providing a proper output signal (I

bus compatible) in order to disable the ICs under

fault and/or to alert

µcontroller by means of warn-

ing messages.

This is preliminary information on a new product now in development or undergoing evaluation. Details are subject to change without notice.

December 1999

®

GND

SDA

SCL

ADD

W

AUX1 IN

AUX1 OUT

AUX2 IN

AUX2 OUT

CH1-

CH2-

CH2+

CH3-

CH3+

CH4-

CH4+

CH5+

CH5-

1

3

2

4

5

6

7

8

9

22

21

20

19

18

16

17

15

23

10

24

5V

CH1+

D97AU570

ST-BY

T-CAP

11

14

13

12

CURR. SET. RES.

PIN CONNECTION (Top view)

SO24

MULTIPOWER BCD TECHNOLOGY

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