Component

Recommended

value

Purpose

Larger than

recommended value

Smaller than

recommended value

C1

2.2

µF

Input DC decoupling

Noise at switch-on,

switch-off

C2

470

µF

Ripple rejection.

Degradation of SVR.

C3

0.1

µF

Supply by passing.

Danger of oscillation.

C4

1000

µF

Output coupling.

Higher low frequency

cutoff.

C5

0.1

µF

Frequency stability.

Danger of oscillation

at high frequencies

with inductive loads.

R1

• R2

Setting of gain. (*)

Increase of drain

current.

R2

2.2

Ω

Setting of gain and

SVR.

Degradation of SVR.

R3

1

Ω

Frequency stability.

Danger of oscillation

at high frequencies

with inductive loads.

PRACTICAL CONSIDERATIONS

Printed circuit board

The layout shown in Fig. 2 is recommended. If

different layouts are used, the ground points of input

1 and input 2 must be well decoupled from the

ground of the output through which a rather high

current flows.

Assembly suggestion

No electrical insulation is needed between the

package and the heat-sink. Pin length should be as

short as possible. The soldering temperature must

not exceed 260

°C for 12 seconds.

Application suggestions

The recommended component values are those

shown in the application circuits of Fig. 1. Different

values can be used. The following table is intended

to aid the car-radio designer.

(*) The closed loop gain must be higher than 26dB.

7/9

TDA2008