Examples of bytes sequence TDA7566
26/29 Doc ID 9801 Rev 6
7 Examples of bytes sequence
1 - Turn-on diagnostic - Write operation
2 - Turn-on diagnostic - Read operation
The delay from 1 to 2 can be selected by software, starting from 1ms
3a - Turn-on of the power amplifier with 26dB gain, mute on, diagnostic defeat.
3b - Turn-off of the power amplifier
4 - Offset detection procedure enable
5 - Offset detection procedure stop and reading operation (the results are valid only for the offset
detection bits (D2 of the bytes DB1, DB2, DB3, DB4).
● The purpose of this test is to check if a D.C. offset (2V typ.) is present on the outputs, produced by
input capacitor with anomalous leakage current or humidity between pins.
● The delay from 4 to 5 can be selected by software, starting from 1ms
6 - Current detection procedure start (the AC inputs must be with a proper signal that depends on the
type of load)
7 - Current detection reading operation (the results valid only for the current sensor detection bits - D5 of
the bytes DB1, DB2, DB3, DB4).
● During the test, a sinus wave with a proper amplitude and frequency (depending on the loudspeaker
under test) must be present. The minimum number of periods that are needed to detect a normal
load is 5.
● The delay from 6 to 7 can be selected by software, starting from 1ms.
Start Address byte with D0 = 0 ACK IB1 with D6 = 1 ACK IB2 ACK STOP
Start Address byte with D0 = 1 ACK DB1 ACK DB2 ACK DB3 ACK DB4 ACK STOP
Start Address byte with D0 = 0 ACK IB1 ACK IB2 ACK STOP
X000000X XXX1X0XX
Start Address byte with D0 = 0 ACK IB1 ACK IB2 ACK STOP
X0XXXXXX XXX0XXXX
Start Address byte with D0 = 0 ACK IB1 ACK IB2 ACK STOP
XX1XX11X XXX1X0XX
Start Address byte with D0 = 1 ACK DB1 ACK DB2 ACK DB3 ACK DB4 ACK STOP
Start Address byte with D0 = 0 ACK IB1 ACK IB2 ACK STOP
XX01111X XXX1X1XX
Start Address byte with D0 = 1 ACK DB1 ACK DB2 ACK DB3 ACK DB4 ACK STOP
