TEA6321T NXP Semiconductors, TEA6321T Datasheet - Page 28

• Manufacturer Part Number: TEA6321T
• Manufacturer: NXP Semiconductors

Specifications of TEA6321T

• Lead Free Status / Rohs Status: Compliant

Philips Semiconductors
Loudness filter calculation example
Figure 17 shows the basic loudness circuit with an
external low-pass filter application. R1 allows an
attenuation range of 21 dB while the boost is determined
by the gain stage V
range of +20 to 12 dB.
Defining f
change while switching loudness on/off. The external
resistor R3 for f
R3 = 3.2 k is generated.
For the low-pass filter characteristic the value of the
external capacitor C1 can be determined by setting a
specific boost for a defined frequency and referring the
gain to G
For example: 3 dB boost at f = 1 kHz
G
If a loudness characteristic with additional high frequency
boost is desired, an additional high-pass section has to be
included in the external filter circuit as indicated in the
block diagram. A filter configuration that provides
AC coupling avoids offset voltage problems.
Figure 18 shows an example of the loudness circuit with
bass and treble boost. The calculation of this network is
numeric.
1995 Dec 19
R3
-------------------- -
j
v
Sound fader control circuit
= G
1
=
C1
R1
v(ref)
v
ref
-------------------- -
1 10
at f
=
+ 3 dB = 18 dB; f = 1 kHz and C1 = 100 nF.
10
–
as the frequency where the level does not
------------------------------------------------------------- -
ref
R1
G
------ -
20
ref
v
G
------ -
20
as indicated above.
v
+
. With G
2
R3
. Both result in a loudness control
1 10
–
can be calculated as:
10
G
------ -
20
v
v
= 21 dB and R1 = 33 k ,
G
------ -
20
v
–
R3
28
handbook, halfpage
handbook, halfpage
Fig.18 Loudness circuit with bass and treble boost.
C1
R3
20 k
150 nF
8.2 nF
C KVL
2.2 k
220 nF
Fig.17 Basic loudness circuit.
8
9
8
9
V 1
0 dB
33 k
R1
V 1
0 dB
33 k
R1
Preliminary specification
V 2
MED846
V 2
TEA6321
R2
MED437
R2