TDA7580

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bus compatible devices incorporate an on-chip interface which allows them communicate directly with each oth-

Every component hooked up to the I

other complex function chip. Each of these chips can act as a receiver and /or transmitter on its functionality.

Two pins are used to interface both I

reducing the on-board pin interconnections.

SERIAL PERIPHERAL INTERFACES

The DSP and RDS can have this serial interface, alternative to the I

separate pin for chip select.

The DSP SPI has a ten 24bit-words deep FIFO for both receive and transmit sections, which reduces DSP pro-

cessing overhead even at high data rate.

The serial interface is needed to exchange commands and data over the LAN. During an SPI transfer, data is

transmitted and received simultaneously. A serial clock line synchronizes shifting and sampling of the informa-

tion on the two serial data lines. A slave select line allows individual selection of a slave SPI device.

When an SPI transfer occurs an 8-bit word is shifted out one data pin while another 8-bit character is simulta-

neously shifted in a second data pin.The central element in the SPI system is the shift register and the read data

buffer. The system is single buffered in the transfer direction and double buffered in the receive direction.

The High Speed Serial Synchronous Interface is a module to send and receive data at high rate (up to 9.25Mbit/

s per channel) in order to exchange data between 2 separate TDA7580 chip.

The exchanged data are related to signals that are used to increase reception quality in Car Radio systems,

which make use of Antenna Diversity based upon two separate antenna and tuner sections.

The channel synchronization clock has a programmable duty cycle, so to reduce in-band harmonics noise.

TUNER AGC KEYING DAC (KEYDAC)

This DAC provides the front-end tuner with an analogue signal to be used to control the Automatic Gain Con-

trolled stage, thus giving all time the best voltage dynamic range at the IFADC input.

ASYNCHRONOUS SAMPLE RATE CONVERTER (ASRC)

This hardware module provides a very flexible way to adapt the internal audio rate, to the one of an external

source. It does not require further work off the DSP.

There is no need to explicitly configure the input and the output sample rates, as the ASRC solves this problem

with an automatic Digital Ratio Locked Loop.

Main features are:

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Automatic Tracking of Sample Frequency

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Fully Digital Ratio Locked Loop

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Sampling Clock Jitter Rejection

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Up-conversion up to 1:2 Ratio

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Linear Phase