TDA75610SLV datasheet(18/42 Pages) STMICROELECTRONICS

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Diagnostics functional description

TDA75610SLV

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DocID025599 Rev 6

Diagnostics functional description

4.1

Turn-on diagnostic

It is recommended to activate this function at the turn-on (standby out) through an I2C bus

request. Detectable output faults are:



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 (Figure 23) 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 "standby out" and "diag. enable" commands are both given through a single

programming step, the pulse takes place first (during the pulse the power stage stays 'off',

showing high impedance at the outputs).

Afterwards, when the amplifier is biased, the PERMANENT diagnostic takes place. The

previous turn-on state is kept until a short appears at the outputs.

Figure 23. Turn-on diagnostic: working principle

Figure 24 and 25 show SVR and OUTPUT waveforms at the turn-on (standby out) with and

without turn-on diagnostic.

Figure 24. SVR and output behavior (Case 1: without turn-on diagnostic)

TDA75610SLV Datasheet(PDF) 18 Page - STMicroelectronics