TDA7439

Application suggestions

9/23

Transposing and solving for the external component values we get:

3.1.2

Treble stage

The treble stage is a high-pass filter whose time constant is fixed by an internal resistor

(25 k

Ω typically) and an external capacitor connected between treble pins and ground.

Typical responses are shown in Figure 10 and Figure 11.

3.2

Pin CREF

can be reduced to 4.7 µF if the application requires faster power-on.

3.3

Electrical characteristics

C1

A

V

1

–

2

π Fc Ri Q

⋅⋅

⋅

⋅

------------------------------------------

=

C2

Q

2

C1

⋅

A

V

1

–

Q

2

–

------------------------------

=

R2

A

V

1

–

Q

2

–

2

π C1 Fc A

V

1

–

() Q

⋅⋅

⋅⋅

⋅

----------------------------------------------------------------------

=

Figure 5.

THD vs frequency

Figure 6.