SAA7806 Datasheet, PDF (1/73 Pages) NXP Semiconductors – One chip automotive CD audio device

SAA7806
One chip automotive CD audio device
Rev. 01 — 20 June 2005
Objective data sheet
1. General description
The SAA7806, is a single chip solution CD audio decoder, digital servo, audio DAC,
pre-amp, laser driver and integrated ARM7TDMI-S microcontroller, targeted at automotive
CD applications. The channel decoder design is derived from the SAA7817 DVD decoder
IC, with optimization and design improvements specifically for CD audio (e.g. improved
CD playability). The digital servo, analog pre-amp, laser driver and audio DAC blocks are
improved designs based on the SAA7824 CD decoder IC. Further architectural
enhancements to the design have been made to integrate system functionality and reduce
the system cost of ownership. The SAA7806 IC supports a generic architecture that will
form the basis of future variants in the SAA7806 IC family optimized for different CD
applications.
2. Features
2.1 Hardware features
s Channel decoder based on SAA7817 IC design
s Digital servo based on SAA7824 IC design
s 32-bit embedded ARM7 RISC microcontroller supporting both 32-bit and 16-bit Thumb
instruction sets
s Mask programmed internal program ROM for microcontroller
s Register structure redesigned to utilize the complete 32-bit bandwidth of the integrated
microcontroller bus architecture
s Programmable clock frequency for ARM microcontroller - allowing users to trade-off
power consumption and processing power depending on requirements
s Microcontroller access to digital representations of the diode input signals from the
optical pick up; the microcontroller can also generate the servo output signals RA, FO,
SL and allows the possibility of additional servo algorithms or a complete servo
implementation in software
s Microcontroller access to audio streams; both from the internal CD decoder and an
external stereo auxiliary input (e.g. an analog source from a tuner; converted to digital
via on-chip ADCs) to allow audio processing algorithms in the ARM microcontroller;
e.g. bass boost and volume control
s Two general purpose analog inputs (A_IN_1 and A_IN_2) allowing the ARM
microcontroller access to other external analog signals; e.g. low cost keypad;
temperature sensor; via on-chip ADCs
s Two analog inputs for external audio sources (e.g. tuner) which can be accessed by
the ARM for audio processing
s Slave I²S-bus mode in which the channel decoder can synchronize the CD playback
speed to an input I²S-bus clock