TDA75610DLVPD
Diagnostics functional description
4
Diagnostics functional description
4.1
Turn-on diagnostic
It is strongly recommended to activate this feature at turn-on (standby out) with 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 22) 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 (power stage still in stand-by mode, low,
outputs= high impedance).
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 22. Turn - on diagnostic: working principle
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Figure 23 and 24 show SVR and OUTPUT waveforms at the turn-on (stand-by out) with and
without turn-on diagnostic.
Figure 23. SVR and output behavior (Case 1: without turn-on diagnostic)
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PERMITTED TIME
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