TDA3190 Datasheet, PDF (7/9 Pages) STMicroelectronics – COMPLETE TV SOUND CHANNEL

TDA3190
APPLICATION INFORMATION
The electrical characteristics of the TDA3190 re-
main almost constant over the frequency range 4.5
to 6 MHz, therefore it can be used in all television
standards (FM mod.). The TDA3190 has a high
input impedance,so it can work with a ceramic filter
or with a tuned circuit that provide the necessary
input selectivity.
The value of the resistors connected to pin 9,
determine the AC gain of the audio frequency am-
plifier. This enables the desired gain to be selected
in relation to the frequency deviation at which the
output stage of the AF amplifier, must enter into
Figure 16 : Typical Application Circuit
clipping.
Capacitor C8, connected between pins 10 and 11,
determines the upper cutoff frequency of the audio
bandwidth.To increase the bandwidth the values of
C8 and C7 must be reduced, keeping the ratio
C7/C8 as shown in the table of fig. 16.
The capacitor connected between pin 16 and
ground, together with the internal resistor of 10 KΩ
forms the de-emphasis network. The Boucherot
cell eliminates the high frequency oscillations
caused by the inductiveload and the wires connect-
ing the loudspeaker.
Figure 17 : P.C. Board and Component Layout of the Circuit shown in Figure 16 (1 : 1 scale)
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