AS3517

Introduction
The MAS 35x9F is a single-chip, low-power MPEG layer 2/3 and MPEG2-AAC audio stereo decoder. It also contains the G.729 Annex A speech compression and decompression technology for use in memorybased or broadcast applications. Additional functionality is achievable via download software (e.g., CELP voice decoder, Micronas SC4 (ADPCM) encoder/decoder).
FeaturesFirmware– MPEG 1/2 layer 2 and layer 3 decoder– Extension to MPEG 2 layer 3 for low sampling rates (“MPEG 2.5”)– Extraction of MPEG Ancillary Data– MPEG 2 AAC decoder (low-complexity profile)– Micronas G.729 Annex A speech compression and decompression– Master or slave clock operation– Adaptive bit rates (bit rate switching)– Intelligent power management (processor clock is dependent on sampling frequencies)– SDMI-compliant security technology– Stereo channel mixer– Bass, treble, and loudness function– Micronas Bass (MB)– Automatic Volume Control (AVC)Interfaces– Two serial asynchronous interfaces for bit streams and uncompressed digital audio– Parallel handshake bit stream input– Serial audio output via I2S and related formats– S/PDIF data input and output– Controlling via I2C interfaceHardware
Features– Two independent embedded DC/DC converters, (e.g., for DSP and flash RAM supply)– Low DC/DC converter start-up voltage (0.9 V)– DC converter efficiency up to 95%– Battery voltage monitor– Low supply voltage down to 2.2 V– Low power dissipation, e.g., 87 mW (128kBit/s, 44.1 kHz, Headphone playback)– High-performance RISC DSP core– On-chip crystal oscillator– Hardware power management and power-off functions– Microphone amplifier– Stereo A/D converter for FM/AM-radio and speech input– CD quality stereo D/A converter– Headphone amplifier– Noise and power-optimized volume– External clock or crystal frequency of 13...28 MHz– Standby current < 10 µA