Description of the input part

TDA7501

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3.1

Input Stages

The device offers several input stages for the different signals which have to be handled by

the system. A quasi differential input (see Figure 4) can be used for (external) CD changer.

The two mono differential inputs allow the connection of phone & navigation (see Figure 5)

or it could be used as fully differential stereo input. Additionally a single-ended stereo input

is available for Cassette applications. The lower part of the input section is dedicated to the

tuner signals. Another quasi differential input (see Figure 6) is used to connect AM and FM

referred to the tuner reference (Tuner). This concept supports also double tuner systems.

Also two seperate level inputs are present which are followed by level-shifters to allow the

use of the TDA7500's ADCs. For AM noise blanking an envelope detector driven by the AM

IF is also available.

Figure 4.

Quasi differential input-stage.

Figure 5.

Mono differential input-stage.

Figure 6.

Differential input-stage for AM/FM.