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TDA7575PD

Examples of bytes sequence

1 - Turn-On diagnostic - Write operation

2 - Turn-On diagnostic - Read operation

The delay from 1 to 2 can be selected by software, starting from T.B.D. ms

3a - Turn-On of the power amplifier with mute on, diagnostic defeat.

3b - Turn-Off of the power amplifier

4 - Offset detection procedure enable

5 - Offset detection procedure stop and reading operation (the results are valid only for the offset detection bits

(D2 of the bytes DB1, DB2, DB3, DB4).

capacitor with anomalous leackage current or humidity between pins.

DIAGNOSTICS FUNCTIONAL DESCRIPTION:

a) TURN-ON DIAGNOSTIC.

– SHORT TO GND

– SHORT TO Vs

– SHORT ACROSS THE SPEAKER

– OPEN SPEAKER

To verify if any of the above misconnections are in place, a subsonic (inaudible) current pulse (fig. A) is internally

generated, sent through the speaker(s) and sunk back.The Turn On diagnostic status is internally stored until a

successive diagnostic pulse is requested (after a I2C reading).

If the "stand-by out" and "diag. enable" commands are both given through a single programming step, the pulse

takes place first (power stage still in stand-by mode, low, outputs= high impedance).

Start

Address byte with D0 = 0

ACK

IB1 with D6 = 1

ACK

IB2

ACK

STOP

Start

Address byte with D0 = 1

ACK

DB1

ACK

DB2

ACK

STOP

Start

Address byte with D0 = 0

ACK

IB1

ACK

IB2

ACK

STOP

X000XXXX

XXX1XX1X

Start

Address byte with D0 = 0

ACK

IB1

ACK

IB2

ACK

STOP

X0XXXXXX

XXX0XXXX

Start

Address byte with D0 = 0

ACK

IB1

ACK

IB2

ACK

STOP

XX1XX1XX

XXX1XXXX

Start

Address byte with D0 = 1

ACK

DB1

ACK

DB2

ACK

STOP