TDA7404

Description of functionality

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4

Description of functionality

4.1

Input stages

Most of the input stages have remained the same as in preceding ST-Audioprocessors with

exception of the CD-inputs (see Figure 3). In the meantime there are some CD-players in

the market which have a significant high source-impedance which effects strongly the

common-mode-rejection of the normal differential input stage.

The additional buffer of the TDA7404 Diff:

●

input avoids this drawback and offers the full common-mode-rejection even with those

CD-players.

Figure 3.

Input stages diagram

1.

It is possible that the Differential input is switched a single ended input (SE4) like SE1.. 3.

Diffin+

/(SE 4)

Inga in

28k

28k

28k

28k

Diffgnd

Mono+

Mono -

SE1

SE2

SE3