TDA7563PD

8/21

Figure 17. Power Dissipation vs. Average

Ouput Power (Audio Program

Simulation, 4

Ω)

Figure 18. Power Dissipation vs. Average

Ouput Power (Audio Program

Simulation, 2

Ω)

01

234

5

Po (W)

0

5

10

15

20

25

30

35

40

45

Ptot (W)

Vs = 14 V

RL = 4 x 4 Ohm

GAUSSIAN NOISE

STD MODE

HI-EFF MODE

CLIP

START

0

1

2

3

45

6789

Po (W)

0

10

20

30

40

50

60

70

80

90

Ptot (W)

Vs = 14 V

RL = 4 x 2 Ohm

GAUSSIAN NOISE

STD MODE

HI-EFF MODE

CLIP

START

3

Diagnostics Functional Description:

a) TURN-ON DIAGNOSTIC

– 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 (fig. 19) is inter-

nally 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 "stand-by 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 19. Turn - On diagnostic: working principle

CH-

CH+

Isource

Vs~5V

Isink

t (ms)

I (mA)

Isink

Isource

~100mS

Measure time