1999 Jun 30
14
Philips Semiconductors
Product specification
2
×
24 W BTL or 4
×
12 W single-ended
car radio power amplifier
TDA8561Q
Mode select switch
To avoid switch-on plops, it is advised to keep the amplifier
in the mute mode during >100 ms (charging of the input
capacitors at pins 1, 3, 15 and 17.
The circuit in Fig.11 slowly ramps up the voltage at the
mode select switch pin when switching on and results in
fast muting when switching off.
Fig.11 Mode select switch circuitry.
handbook, halfpage
100 k
Ω
MGA708
47
µ
F
10 k
Ω
100
Ω
mode
select
switch
VP
Fig.12 Total harmonic distortion as a function of output power; V
P
= 14.4 V, R
L
= 4
Ω.
(1) f = 10 kHz.
(2) f = 1 kHz.
(3) f = 100 Hz.
10
2
MGA709
10
1
10
1
10
2
10
1
10
P (W)
o
10
2
1
10
2
THD
(%)
(1)
(2)
(3)
