Datasheet

TDA7491LP Applications information
Doc ID 13541 Rev 5 25/37
5.2 Mode selection
The three operating modes, defined below, of the TDA7491LP are set by the two inputs
STBY (pin 20) and MUTE (pin 21) as shown in Ta bl e 6.
● Standby mode: all circuits are turned off, very low current consumption.
● Mute mode: inputs are connected to ground and the positive and negative PWM
outputs are at 50% duty cycle.
● Play mode: the amplifiers are active.
The protection functions of the TDA7491LP are implemented by pulling down the voltages of
the STBY and MUTE inputs shown in Figure 27. The input current of the corresponding pins
must be limited to 200 µA.
Figure 27. Standby and mute circuits
Figure 28. Turn-on/off sequence for minimizing speaker “pop”
Table 6. Mode settings
Mode Voltage level on pin STBY Voltage level on pin MUTE
Standby L
(1)
1. Refer to V
STBY
and V
MUTE
in Table 5: Electrical specifications on page 10 for the drive levels for L and H
X (don’t care)
Mute H
(1)
L
Play H H
STBY
MUTE
0 V
3.3 V
C7
2.2 µF
R2
30 kΩ
Standby
0 V
3.3 V
C15
2.2 µF
R4
30 kΩ
Mute
TDA7491LP