TDA7406T datasheet(9/49 Pages) STMICROELECTRONICS

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TDA7406T

DESCRIPTION OF THE AUDIOPROCESSOR PART

2.1 Input stages

In the basic configuration there is a source-Selector with 8 inputs: one pseudo-differential (CDC), three single

ended stereo (MD, CD, Tape), three single-ended mono (PHONE, NAVI, TIM) plus the “tuner” input. The tuner

input takes the signal from either MPX1 or MPX2/AM pins (through the stereodecoder) see Fig. 1.

2.1.1 Pseudo-differential stereo Input (PD)

The PD input is implemented as a buffered pseudo-differential stereo stage with 100k

Ω input-impedance at

each input pin. This input is also configurable as single-ended stereo input (CDC, see pin-out). The common

input-pin, PD- features a fast charge switch to speed up the charge time of external capacitors. This switch is

released the first time the input-selector data-byte (0) is assessed.

2.1.2 Single-ended stereo Inputs, single-ended mono inputs and FM-MPX input

All single ended inputs have an input impedance of 100k

Ω. The AM-pin can be connected to the input of the

stereo-decoder in order to use the AM-noiseblanker and AM-High-Cut feature. As input “Tuner” for the input se-

lector either the stereo-decoder output or the AM-pin is selectable.

2.1.3 Mixing Selector

It is possible to enable/disable the mixing feature (ratio 50%) at the outputs stages between whichever input

source and one of the following signals: Beep, Phone, Navigator and Tuner/TIM.

2.1.4 Beep Generator

There are four possible selectable beeping frequencies: 600Hz, 780Hz, 1.56KHz and 2.4KHz.

Figure 1. Input-stages

TDA7406T 数据表(PDF) 9 Page - STMicroelectronics