TDA7439 STMicroelectronics, TDA7439 Datasheet - Page 8

• Manufacturer Part Number: TDA7439
• Description: IC PROCESSOR AUDIO DGTL 30-SDIP
• Manufacturer: STMicroelectronics
• Type: Audio Processorr

Specifications of TDA7439

• Applications: Automotive Systems
• Mounting Type: Through Hole
• Package / Case: 30-SDIP (0.400", 10.16mm)
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 497-8866-5; TDA7439

Application suggestions
3
3.1
3.1.1
8/23
Application suggestions
The first and the last stages are volume control blocks. The control range is 0 to -47 dB and
mute for the first stage and 0 to -79 dB and mute for the last one. Both control blocks have a
step resolution of 1 dB.
This very high resolution allows the implementation of systems free from any noisy
acoustical effect.
The TDA7439 audio processor provides 3 bands of tone control (bass, mid-range and
treble).
Tone control
Bass, mid-range stages
The bass and the mid-range cells have the same structure.
However, the bass cell has an internal resistor R
has an internal resistor R
Several filter types can be implemented by connecting external components to the bass/mid
IN and OUT pins.
Typical responses are shown in
Figure 4.
Figure 4.
(R1 (internal) and R2, C1, C2 (external)) then the centre frequency f
maximum boost and the filter Q factor are computed as follows:
Q
A
f C
refers to the basic T-type band-pass filter. Starting from the filter component values
V
=
=
=
-------------------------------------------------
Bass/mid-range filter implementation
---------------------------------------------------------------- -
2 π
R2C2
----------------------------------------------------------- -
R1 R2 C1 C2
R2C1
⋅ ⋅
R2C1
⋅
+
R1 R2 C1 C2
+
R2C1
⋅
R2C2
+
⋅
1
R2C2
M
⋅
of typically 25 kΩ.
+
⋅
RiC1
Figure
⋅
C
IN
1
8,
Ri internal
Figure 9
R
D95AU313
B
2
of typically 44 kΩ whilst the mid-range cell
OUT
and
C
2
Figure
11.
C
, the gain Av at
TDA7439