NXP Semiconductors TFA9812 Stereo Amplifier User Manual


 
TFA9812_2 © NXP B.V. 2009. All rights reserved.
Preliminary data sheet Rev. 02 — 22 January 2009 13 of 66
NXP Semiconductors
TFA9812
BTL stereo Class-D audio amplifier with I
2
S input
8.3 Power-up/power-down
8.3.1 Power-up
Figure 3 and Table 10 describe the power-up timing while Table 11 shows the pin control
for initiating a power-up reset.
[1] Mute in Legacy mode is controlled by AVOL pin.
Fig 3. Power-up/power-down timing
external
voltage
supplies
POWERUP
pin
I
2
C
available
ENABLE
pin
PWM
outputs
t
wake
t
d(on)
t
d(mute_off)
t
d(soft_mute)
010aaa219
soft mute
setting in
I
2
C mode
AVOL pin
in Legacy
mode
Operating
mode active
Table 10. Power-up/power-down timing
Symbol Parameter Conditions Min Typ Max Unit
t
wake
wake-up
time
I
2
C control - 4 - ms
t
d(on)
turn-on
delay time
- 70 - 135 ms
t
d(mute_off)
mute off
delay time
- - - 128/f
s
s
t
d(soft_mute)
Soft mute
delay time
I
2
C control - - 128/f
s
s
legacy
control
[1]
-15-ms