TDA7501

Description of the output part

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Description of the output part

The TDA7501 has 6 independent outputstage with volume control. The first 4 (main) outputs

have an input selector which allows to select besides the DAC outputs CD direct or

Phone/Navigation-mix. In addition one can mix the SPKR1 with Phone/Navigation so that

traffic or navigation announcements can bypass the DSP (see figure 8).

The TDA7500 CODEC outputs have a maximum output voltage of 0.5Vrms . To obtain

4Vrms , (in the dual supply mode only) the signal is first amplified to have a reference

amplitude of 2V rms. The following volume stage offers up to 15dB gain which gives along

with the programmable 6dB gain in the output-stage enough overdrive capability. To achieve

the maximum output swing of 4Vrms the device must be supplied with an additional supply

maximum.

Figure 10.

Output part.

4.1

Overall gain structure

The overall gain structure of the TDA7501 can be shown in its target application together

with the V225.

The output part in level select (D6/4) offers an additional adaption to the DSP's output level