PRELIMINARY DATA SHEET MAS 3587F
Micronas 5
MPEG Layer 3 Audio Encoder/Decoder
This data sheet applies to MAS 3587F version B2.
Release Note: Revision bars indicate significant
changes to the previous edition.
1. Introduction
The MAS 3587F is a single-chip MPEG layer 3 audio
encoder/decoder designed for use in memory-based
recording/playback applications, e.g. MP3 record/play-
back equipment. The IC contains a DSP engine with
embedded RAM and ROM. It provides flexible digital
interfaces for serial and S/PDIF audio data input and
output. Also integrated are power management func-
tions and two DC/DC converters for single cell power
supply. A high-quality stereo D/A converter and a ste-
reo A/D converter on chip provide the analog functions
required in an advanced portable audio player.
In encoding mode, audio data is input via the inte-
grated A/D converter, serial PCM, or S/PDIF interface.
The compressed digital data stream is sent via the par-
allel interface. In decoding mode, compressed digital
data streams are accepted in the parallel or serial for-
mat. The audio data is output via the high quality D/A
converter. A digital output in serial PCM format and/or
S/PDIF format is also provided.
Thus, the MAS 3587F provides a true ’ALL-IN-ONE’
solution that is ideally suited for highly optimized mem-
ory based music recorders.
Additional functionality is achieved via download soft-
ware (e.g. Micronas SC4 encoder/decoder). SC4 is a
proprietary Micronas speech codec technology based
on ADPCM. The codec can be downloaded to the
MAS 3587F to allow high quality speech recording and
playing back at various sampling rates. (Please con-
tact your local Micronas Sales Representative about
availability of SC4 downloads).
In MPEG 1 (ISO 11172-3), three hierarchical layers of
compression have been standardized. The most
sophisticated and complex, layer 3, allows compres-
sion rates of approximately 12:1 for mono and stereo
signals while still maintaining CD audio quality.
The MAS 3587F is available in the PMQFP64 pack-
age.
1.1. Features
Firmware
– MPEG 1/2 layer 3 encoder
– Encoding with adaptive bit rate up to 192 kbit/s
– MPEG 1/2 layer 2 and layer 3 decoder
– Decoder-extension to MPEG 2 layer 3 for low bit
rates (“MPEG 2.5”)
– Extraction of MPEG Ancillary Data
– Adaptive bit rates (bit rate switching)
– SDMI-compliant security technology for decoder
– Stereo channel mixer
– Bass, treble and loudness function
– Micronas Dynamic Bass (MDB)
– Automatic Volume Correction (AVC)
Interfaces
– 2 serial asynchronous interfaces for bitstreams and
uncompressed digital audio
– Parallel handshake bit stream input/output
– Serial audio output via I
2
S and related formats
– S/PDIF audio input
– S/PDIF audio output
– Controlling via I
2
C interface
Hardware 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 2.5 V for decoder,
3.5 V for encoder)
– Low power dissipation (down to 70 mW for decoder,
down to 450 mW for MPEG 1 encoder)
– Hardware power management and power-off func-
tions
– Microphone amplifier
– Stereo A/D converter for FM/AM-radio and speech
input
– CD quality stereo D/A converter
– Headphone amplifier
– On-chip crystal oscillator
– External clock or crystal frequency of 13...28 MHz
– Standby current < 10 µA
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