TELEFUNKEN Semiconductors

TDA 4480-C

2

Preliminary Information

Pin Configuration

Pin

Symbol

Function

1–2

Vision-IF-carrier input

3

Intercarrier input 5.74 MHz

4

AGC time constant

5

Intercarrier output 5.74 MHz

6

Standard switch

7

AF output 1

8-9

Phase tank circuit 5.74 MHz

10

VC0 tank circuit

Pin

Symbol

Function

11

Ground

12-13

Phase tank circuit 5.5 MHz

14

AF output 2

15

Intercarrier output 5.5 MHz

16

Supply voltage

17

Intercarrier input 5.5 MHz

18-19

Sound-IF-carrier input

20

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

Value

Unit

Supply voltage

Pin 16

10 to 13.5

V

Supply current

Pin 16

80

mA

External voltage

Pin 6

Pin 1, 2, 3, 4, 5, 7, 8, 9, 12,

13, 14, 15, 17, 18, 19

6

V

V

Power dissipation

(in soldered position)

1

W

Junction temperature

125

Ambient temperature range

- 25 to + 70

Storage temperature range

- 25 to + 125