Test and application information, Test conditions, Btl application – Philips TDA8543 User Manual
Page 7: Se application, General remark
1997 Jun 12
7
NXP Semiconductors
Product specification
2 W BTL audio amplifier
TDA8543
Notes to the AC characteristics
1. Gain of the amplifier is
in test circuit of Fig.4.
2. The noise output voltage is measured at the output in a frequency range from 20 Hz to 20 kHz (unweighted), with
a source impedance of R
S
= 0
Ω at the input.
3. Supply voltage ripple rejection is measured at the output, with a source impedance of R
S
= 0
Ω at the input.
The ripple voltage is a sine wave with a frequency of 1 kHz and an amplitude of 100 mV (RMS), which is applied
to the positive supply rail.
4. Supply voltage ripple rejection is measured at the output, with a source impedance of R
S
= 0
Ω at the input.
The ripple voltage is a sine wave with a frequency between 100 Hz and 20 kHz and an amplitude of 100 mV (RMS),
which is applied to the positive supply rail.
5. Output voltage in mute position is measured with an input voltage of 1 V (RMS) in a bandwidth of 20 kHz, so including
noise.
2
R2
R1
--------
×
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 envelope;
the maximum sine wave power dissipation
for T
amb
= 25
°C is:
For T
amb
= 60
°C the maximum total power dissipation is:
See the power derating curve illustrated in Fig.3.
BTL application
T
amb
= 25
°C if not specially mentioned, V
CC
= 5 V,
f = 1 kHz, R
L
= 8
Ω, G
v
= 20 dB, audio band-pass
22 Hz to 22 kHz.
The BTL application diagram is shown in Fig.4.
The quiescent current has been measured without
any load impedance. The total harmonic distortion
as a function of frequency was measured with a low-pass
filter of 80 kHz. The value of capacitor C2 influences
the behaviour of the SVRR at low frequencies, increasing
the value of C2 increases the performance of the SVRR.
The figure of the mode select voltage (V
ms
) as a function
of the supply voltage shows three areas; operating, mute
and standby. It shows, that the DC-switching levels
of the mute and standby respectively depends
on the supply voltage level.
SE application
T
amb
= 25
°C if not specially mentioned, V
CC
= 7.5 V,
f = 1 kHz, R
L
= 4
Ω, G
v
= 20 dB, audio band-pass
22 Hz to 22 kHz.
The SE application diagram is shown in Fig.14.
The capacitor value of C3 in combination with the load
impedance determines the low frequency behaviour.
The total harmonic distortion as a function of frequency
was measured with low-pass filter of 80 kHz. The value
of capacitor C2 influences the behaviour of the SVRR
at low frequencies, increasing the value of C2 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 of HF radiation in radio
circuit applications, a small capacitor can be connected
in parallel with the feedback resistor; this creates a
low-pass filter.
150
25
–
55
----------------------
2.27 W
=
150
60
–
55
----------------------
1.63 W
=