TDA7566

Diagnostics functional description

Doc ID 9801 Rev 6

13/29

Figure 17.

SVR and output behavior (case 1: without turn-on diagnostic)

Figure 18.

SVR and output pin behavior (case 2: with turn-on diagnostic)

The information related to the outputs status is read and memorized at the end of the

current pulse top. The acquisition time is 100 ms (typ.). No audible noise is generated in the

process. As for short to GND / Vs the fault-detection thresholds remain unchanged from

26 dB to 12 dB gain setting. They are as follows:

Figure 19.

Thresholds for short to GND/VS

Bias (power amp turn-on)

t

Diagnostic Enable

(Permanent)

Permanent diagnostic

acquisition time (100mS Typ)

Permanent Diagnostics data (output)

permitted time

I2CB DATA

Vsvr

Out

FAULT

event

Read Data

Bias (power amp turn-on)

permitted time

Turn-on diagnostic

acquisition time (100mS Typ)

t

Read Data

Permanent diagnostic

acquisition time (100mS Typ)

Permanent Diagnostics data (output)

permitted time

Diagnostic Enable

(Turn-on)

Turn-on Diagnostics data (output)

permitted time

I2CB DATA

Vsvr

Out

Diagnostic Enable

(Permanent)

FAULT

event

D01AU1253

S.C. to GND

x

S.C. to Vs

0V

1.8V

VS-1.8V

VS

x

Normal Operation

1.2V

VS-1.2V