TDA7563B

Diagnostics functional description

Doc ID 12733 Rev 6

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Figure 21.

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 30

dB to 16 dB gain setting. They are as follows:

Figure 22.

Thresholds for short to GND/VS

Concerning short across the speaker / open speaker, the threshold varies from 30 dB to 16

dB gain setting, since different loads are expected (either normal speaker's impedance or

high impedance). The values in case of 30 dB gain are as follows:

Figure 23.

Thresholds for short across the speaker/open speaker

If the line-driver mode (Gv= 16 dB and line driver mode diagnostic = 1) is selected, the same

thresholds will change as follows:

Figure 24.

Thresholds for line-drivers