TDA8547 Philips Semiconductors, TDA8547 Datasheet - Page 9

• Manufacturer Part Number: TDA8547
• Description: 2 x 1 W BTL audio amplifier with output channel switching
• Manufacturer: Philips Semiconductors

Philips Semiconductors
TEST AND APPLICATION INFORMATION
Test conditions
Because the application can be either Bridge-Tied Load
(BTL) or Single-Ended (SE), the curves of each
application are shown separately.
The thermal resistance = 55 K/W for the DIP16; the
maximum sine wave power dissipation for T
is:
For T
BTL application
T
f = 1 kHz, R
22 Hz to 22 kHz.
The BTL application circuit is illustrated in Fig.4.
The quiescent current has been measured without any
load impedance and both channels driven. When one
channel is active the quiescent current will be halved.
The total harmonic distortion as a function of frequency
was measured using a low-pass filter of 80 kHz.
The value of capacitor C3 influences the behaviour of the
SVRR at low frequencies: increasing the value of C3
increases the performance of the SVRR.
The figure of the MODE voltage (V
the supply voltage shows three areas; operating, mute
and standby. It shows, that the DC-switching levels of the
mute and standby respectively depend on the supply
voltage level. The figure of the SELECT voltage (V
as a function of the supply voltage shows the voltage
levels for switching the channels in the active, mute or
standby mode.
1997 Oct 07
150 60
--------------------- -
amb
2
channel switching
150 25
--------------------- -
55
–
amb
= 25 C if not specially mentioned, V
55
–
1 W BTL audio amplifier with output
= 60 C the maximum total power dissipation is:
=
L
1.7 W
=
= 8 , G
2.3 W
v
= 20 dB, audio band-pass
MODE
) as a function of
CC
amb
= 5 V,
= 25 C
SELECT
)
9
SE application
T
f = 1 kHz, R
22 Hz to 22 kHz.
The SE application circuit is illustrated in Fig.16.
Increasing the value of electrolytic capacitor C3 will result
in a better channel separation. Because the positive
output is not designed for high output current (2
low load impedance ( 16 ), the SE application with
output capacitors connected to ground is advised.
The capacitor value of C6/C7 in combination with the load
impedance determines the low frequency behaviour.
The THD as a function of frequency was measured using
a low-pass filter of 80 kHz. The value of capacitor C3
influences the behaviour of the SVRR at low frequencies:
increasing the value of C3 increases the performance of
the SVRR.
General remark
The frequency characteristic can be adapted by
connecting a small capacitor across the feedback
resistor. To improve the immunity to HF radiation in radio
circuit applications, a small capacitor can be connected in
parallel with the feedback resistor (56 k ); this creates a
low-pass filter.
amb
= 25 C if not specially mentioned, V
L
= 4 , G
v
= 20 dB, audio band-pass
Preliminary specification
TDA8547
CC
= 7.5 V,
I
o
) at