Philips Semiconductors
14. Application information
TDA8942P
2 x 1.5 W stereo BTL audio amplifier
Rs
220 nF
Symmetrical
input
Ci
220 nF
Rs
220 nF
Asymmetrical
input
Ci
signal
GND
220 nF
IN1− 13
1.5
nF
3
IN1+
IN2− 12
1.5
nF
VCC
R
11
IN2+
MODE 4
C1
MICROCONTROLLER
C2
MODE
Standby
Mute
On
C1 C2
00
01
10
R
signal
GND
SVR 14
10
µF
100 nF
1
9
30 kΩ
+VCC
1000 µF
Ri
45 kΩ
1/2 VCC
Ri
45 kΩ
−
−+
+
−
+
1/2 VCC
+
−
TDA8942P
30 kΩ
15 OUT1−
2 OUT1+
RL
16 Ω
Ri
45 kΩ
1/2 VCC
Ri
45 kΩ
−
−+
+
−
+
1/2 VCC
+
−
STANDBY/
MUTE LOGIC
VCC
30 kΩ
7 OUT2−
10 OUT2+
20 kΩ
1/2 VCC
20 kΩ
SHORT CIRCUIT
AND
TEMPERATURE
PROTECTION
RL
16 Ω
16
8
GND
MGL999
Fig 14. Application diagram.
14.1 Printed-circuit board (PCB)
14.1.1 Layout and grounding
For a high system performance level certain grounding techniques are essential.
The input reference grounds have to be tied with their respective source grounds and
must have separate tracks from the power ground tracks; this will prevent the large
(output) signal currents from interfering with the small AC input signals.
The small-signal ground tracks should be physically located as far as possible from
the power ground tracks. Supply and output tracks should be as wide as possible for
delivering maximum output power.
9397 750 06862
Product specification
Rev. 02 — 14 March 2000
© Philips Electronics N.V. 2000. All rights reserved.
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