TDA7501 datasheet(9/18 Pages) STMICROELECTRONICS

9 / 18 page

TDA7501

Figure 6. Level-diagram.

TDA7500

TDA7501

Figure 7. Reference voltage generation

REFERENCE CONCEPT

For the input section the TDA7501 generates the

internal reference voltage by multiplying the V33

voltage by 1.2575.

The V33 voltage is also buffered and fed back to

the CODEC where it is used to generate all nec-

essary references. For best performance it is rec-

ommended to filter the V33 reference pin by

means of a passive second order lowpass as

shown in figure 7 This concept allows a direct DC

coupling between the TDA7501 and the DSP

because of the accurate matching of DC levels.

On the output side the TDA7501 offers two main

modes: a single supply and a dual supply mode.

Dual supply mode

In this mode the outputs are able to provide up to

4V rms with a minimum supply VCC of 12V as

well as a output reference voltage set to half of

VCC (bit D0 of the mode select byte set to ’1’). If

the switch D1/byte mode select is open the out-

put reference voltage must be defined externally

e.g. a zener diode with RC-lowpass. If the switch

is closed the reference voltage will be half of V cc

and only an external capacitor has to be added.

TDA7501

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TDA7501 Datasheet(PDF) 9 Page - STMicroelectronics