digital domain and performs AM/FM processing

and audio/sound processing. Thanks to this, it is

possible to process any audio source as well ana-

log as digital in parallel, to record FM mono for

traffic information, telephone response, naviga-

tion and RDS. Finally the digital signals are D/A

converted and sent to the TDA7501 for the final

level adjustment and for the analog volume con-

trol.

DLY

DLY

DLY

HP

PEQ

T

B

LD

DRC

RM

ANR

SM

+

DLY

HP

PEQ

T

B

LD

DRC

ANR

SM

DLY

LP

Audio

noise

reduction

Dynamic

range

compression

Loudness Bass

Treble Parametric

equaliser

Soft

mute

Routing

matrix

Delay

Stereo

input

RF

CF

LF

RR

LR

SW

Figure 1. Software Block Diagram of Audio & Sound Processing

TDA7501

ANALOG INPUT

TDA7500

FRONT END

TDA7421

AUDIO POWER

DISPLAY

MICRO

DIGITAL OUT

MAIN

MICRO

DRAM/

SRAM

EEPROM/

FLASH

DIGITAL IN

SPDIF

I

D98AU946A

A/D

D/A

Figure 2. Block Diagram of Car Amplifier Audio Sub-System.

TDA7500

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