TDA7564

18/20

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 26dB gain, mute on, diagnostic defeat, High eff. mode both channels..

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).

s

The purpose of this test is to check if a D.C. offset (2V typ.) is present on the outputs, produced by input

capacitor with anomalous leakage current or humidity between pins.

s

The delay from 4 to 5 can be selected by software, starting from T.B.D. ms

6 - Current detection procedure start (the AC inputs must be with a proper signal that depends on the type of

load)

7 - Current detection reading operation (the results valid only for the current sensor detection bits - D5 of the

bytes DB1, DB2, DB3, DB4).

s

During the test, a sinus wave with a proper amplitude and frequency (depending on the loudspeaker

under test) must be present. The minimum number of periods that are needed to detect a normal load

is 5.

s

The delay from 6 to 7 can be selected by software, starting from T.B.D. ms.

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

DB3

ACK

DB4

ACK

STOP

Start

Address byte with D0 = 0

ACK

IB1

ACK

IB2

ACK

STOP

X000000X

XXX1X011

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

XX1XX11X

XXX1X0XX

Start

Address byte with D0 = 1

ACK

DB1

ACK

DB2

ACK

DB3

ACK

DB4

ACK

STOP

Start

Address byte with D0 = 0

ACK

IB1

ACK

IB2

ACK

STOP

XX01111X

XXX1X1XX

Start

Address byte with D0 = 1

ACK

DB1

ACK

DB2

ACK

DB3

ACK

DB4

ACK

STOP