Overview

TDA7580

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Overview

The algorithm is self-adaptive, thus it requires no “on-the-field” adjustments after the

parameters optimization.

The chip embeds a

Band Pass Sigma Delta Analogue to Digital Converter for 10.7MHz IF

conversion from a “tuner device” (the TDA7515 is highly recommended).

The 24bit DSP allows flexibility in the algorithms implementation, thus giving some freedom

for customer required features. The total processing power offers a significant headroom for

customer’s software requirement, even when the channel equalization and the decoding

software is running. the program and data memory space can be loaded from an external

The oscillator module works with an external 74.1MHz quartz crystal. It has very low electro

magnetic interference, as it introduces very low distortion, and in any case harmonics fall

outside the radio bandwidth.

The companion tuner device receives the reference clock through a differential ended

interface, which works off the oscillator module by properly dividing down the master clock

frequency. That allows the overall system saving an additional crystal for the tuner.

After the IF conversion, the digitized baseband signal passes through the base band

processing section, either FM or AM, depending on the listener selection. The FM base

band processing comprises of stereo decoder, spike detection and noise blanking. The AM

noise blanking is fully software implemented.

The internal RDS filter, demodulator and decoder features complete functions to have the

start-up, so that RDS can work in background and in parallel with other DSP processing.

This mode (RDS only) allows current consumption saving for low power application modes.

well as RDS data interface. The DSP SPI block embeds a 10 words FIFO for both transmit

and receive channels, to lighten the DSP task and frequently respond to the interrupt from

the control interface.

Serial audio interface (SAI) is the ideal solution for the audio data transfer, both transmit and

receive: either master or slave. The flexibility of this module gives a wide choice of different

clocks allows the use of TDA7580 as general purpose digital audio processor.

A fully asynchronous sample rate converter (ASRC) is available as a peripheral prior to

sending audio data out via the SAI, so that internal audio sampling rate (~36kHz and

FM/AM mode) can be adapted by upconversion to any external rate.

also available for a modular system which implements

Dual Tuner Diversity, thus enhancing

the overall system performance. It is about a synchronous serial interface which exchanges

data up to the MPX rate. It has been designed to reduce the electro magnetic interference

toward the sensitive analogue signal from the tuner.

General purpose I/O registers are connected to and controlled by the DSP, by means of

memory map.

A debug and test interface is available for on chip software debug as well as for internal

registers read/write operation.