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

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 connecte d between pin 16 and

ground, together with the internal resistor of 10 K

Ω

forms the de-emphasis network. The Boucherot

cell eliminates the high frequency oscillations

caused by the inductiveload and the wires connect-

ing the loudspeaker.

APPLICATION INFORMATION

Figure 16 : Typical Application Circuit

Figure 17 : P.C. Board and Component Layout of the Circuit shown in Figure 16 (1 : 1 scale)

TDA3190

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