1997 Oct 07 4
Philips Semiconductors Preliminary specification
2 × 1 W BTL audio amplifier with output
channel switching
TDA8547
PINNING
SYMBOL PIN DESCRIPTION
GND1 1 ground, channel 1
OUT1+ 2 positive loudspeaker terminal,
channel 1
MODE 3 operating mode select (standby,
mute, operating)
SVRR 4 half supply voltage, decoupling
ripple rejection
SELECT 5 input for selection of operating
channel
n.c. 6 not connected
OUT2+ 7 positive loudspeaker terminal,
channel 2
GND2 8 ground, channel 2
V
CC2
9 supply voltage, channel 2
OUT2− 10 negative loudspeaker terminal,
channel 2
IN2− 11 negative input, channel 2
IN2+ 12 positive input, channel 2
IN1+ 13 positive input, channel 1
IN1− 14 negative input, channel 1
OUT1− 15 negative loudspeaker terminal,
channel 1
V
CC1
16 supply voltage, channel 1
Fig.2 Pin configuration.
handbook, halfpage
TDA8547
MGK696
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
GND1
OUT1+
MODE
SVRR
SELECT
n.c.
OUT2+
GND2
V
CC2
OUT2−
IN2−
IN2+
IN1+
IN1−
OUT1−
V
CC1
FUNCTIONAL DESCRIPTION
The TDA8547(T) is a 2 × 1 W BTL audio power amplifier
capable of delivering 2 × 1 W output power to an 8 Ω load
at THD = 10% using a 5 V power supply. Using the
MODE pin the device can be switched to standby and
mute condition. The device is protected by an internal
thermal shutdown protection mechanism. The gain can be
set within a range from 6 to 30 dB by external feedback
resistors.
Power amplifier
The power amplifier is a Bridge-Tied Load (BTL) amplifier
with a complementary PNP-NPN output stage.
The voltage loss on the positive supply line is the
saturation voltage of a PNP power transistor, on the
negative side the saturation voltage of a NPN power
transistor. The total voltage loss is <1 V and with a 5 V
supply voltage and an 8 Ω loudspeaker an output power of
1 W can be delivered.
MODE pin
The whole device (both channels) is in the standby mode
(with a very low current consumption) if the voltage at the
MODE pin is >(VCC− 0.5 V), or if this pin is floating. At a
MODE voltage level of less than 0.5 V the amplifier is fully
operational. In the range between 1.5 V and VCC− 1.5 V
the amplifier is in mute condition. The mute condition is
useful to suppress plop noise at the output caused by
charging of the input capacitor.
SELECT pin
If the voltage at the SELECT pin is in the range between
1.5 V and V
CC
− 1.5 V, or if it is kept floating, then both
channels can be operational. If the SELECT pin is set to a
LOW voltage or grounded, then only channel 2 can
operate and the power amplifier of channel 1 will be in the
standby mode. In this case only the loudspeaker at
channel 2 can operate and the loudspeaker at channel 1
will be switched off. If the SELECT pin is set to a
HIGH level or connected to VCC, then only channel 1 can