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TDA7564

S. GND (so) / S. GND (sk) in the above table make a distinction according to which of the 2 outputs is shorted

to ground (test-current source side= so, test-current sink side = sk). More precisely, in Channels LF and RR, so

= CH+, sk = CH-; in Channels LR and RF, so = CH-, sk = CH+ .

In Permanent Diagnostic the table is the same, with only a difference concerning Open Load(*) , which is not

among the recognisable faults. Should an Open Load be present during the device's normal working, it would

be detected at a subsequent Turn on Diagnostic cycle (i.e. at the successive Car Radio Turn on).

FAULTS AVAILABILITY

period of time. If the fault is stable throughout the whole period, it will be sent out. This is true for DC diagnostic

(Turn on and Permanent), for Offset Detector, for AC Diagnostic (the low current sensor needs to be stable to

confirm the Open tweeter).

To guarantee always resident functions, every kind of diagnostic cycles (Turn on, Permanent, Offset, AC) will

but the read data will come from the previous diag. cycle (i.e. The device is in Turn On state, with a short to Gnd,

A correct turn on/off sequence respectful of the diagnostic timings and producing no audible noises could be as

follows (after battery connection):

TURN-ON: (STAND-BY OUT + DIAG ENABLE) --- 500 ms (min) --- MUTING OUT

TURN-OFF: MUTING IN --- 20 ms --- (DIAG DISABLE + STAND-BY IN)