TELEFUNKEN Semiconductors
TDA 4480-C
2
Preliminary Information
Pin Configuration
Pin
1–2
3
4
5
6
7
8-9
10
Symbol
Function
Vision-IF-carrier input
Intercarrier input 5.74 MHz
AGC time constant
Intercarrier output 5.74 MHz
Standard switch
AF output 1
Phase tank circuit 5.74 MHz
VC0 tank circuit
Pin
11
12-13
14
15
16
17
18-19
20
Symbol
Function
Ground
Phase tank circuit 5.5 MHz
AF output 2
Intercarrier output 5.5 MHz
Supply voltage
Intercarrier input 5.5 MHz
Sound-IF-carrier input
n.c.
Circuit Description
The integrated circuit allows the high quality processing of sound carrier for different TV standards. The circuit requires
separate vision and audio carrier inputs. It delivers the output audio signal for mono, two channels or stereo applications.
Audio carrier signal (simple or double carrier, FM and AM) is applied via three stage AGC controlled broad band amplifier
which delivers regulated output signal for two mixing stages. One mixer works for AM-demodulation and AGC-function
whereas the second mixer produces the sound intercarrier IF-frequencies (5.5/5.74 MHz).
Vision carrier signal for the intercarrier generation is delivered from the demodulator tank of the video IF circuit (TDA
4439, TDA 4453). It is then matched via a limiter stage to the FM intercarrier mixer. FM-sound-IF-carrier reaches the
quadrature demodulator via the selection circuit and the following limiter amplifier. The final audio signal is supplied
to the low ohmic output (Pin 7,14) with low pass filter character.
There is a switchable converter for different audio standards (4.5, 6.00 and 6.5 MHZ), which mixes the sound 1P-signal
properly e.g. at 5.5 MHz. The VC0 (Pin 10) must be controlled across the sound output (Pin 7) which includes
AFC-function.
Sound signal at the AM-modulation is introduced via standard switch in the first sound channel, whereas the intercarrier,
converter section and both FM demodulators are switched off. In case of sound IF converter operation, the second sound
channel and the AM-section are switched off. The standard mode is controlled by a tristate signal on Pin 6.
Absolute Maximum Ratings
Reference point Pin 11, unless otherwise specified
Parameters
Symbol
V
S
I
S
V
ext
Value
10 to 13.5
80
V
S
Unit
V
mA
V
Supply voltage
Supply current
External voltage
Pin 16
Pin 16
Pin 6
V
ext
6
V
!
P
tot
T
j
T
amb
T
stg
1
W
C
C
C
125
- 25 to + 70
- 25 to + 125